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High pressure and high speed "is the label of die-casting technology, but when it comes to numerical aspects, most people do not have a clear concept. We present the magnitude difference between pressure, speed, and production cycle using quantitative data.   1. Filling pressure: thousands of times difference from "self weight" to "hundreds of megapascals" Pressure is the most essential characteristic of die-casting and the key to ensuring the density of castings.   Gravity casting: The filling pressure of the molten metal only comes from its own liquid column gravity, and the equivalent pressure is usually less than 0.01 MPa; Even in low-pressure casting, the auxiliary pressure is generally in the range of 0.05~0.1MPa, which only plays a role in smooth filling. Pressure casting: divided into two stages: injection propulsion and pressure boosting and holding. The final pressurization and holding pressure of the cold chamber die-casting machine can reach 60-120 MPa, which is equivalent to bearing a pressure of 600-1200 kilograms per square centimeter, thousands of times higher than that of gravity casting.   For example, the tire pressure of a regular household car is about 0.25MPa, and the holding pressure of die-casting is equivalent to 240-480 times the tire pressure. Such immense pressure can not only force the molten metal to fill every fine structure of the mold cavity, but also continuously compensate for metal shrinkage during the solidification process, reducing shrinkage porosity and porosity defects from the root.   2. Charging speed: millisecond level charging from "slow flow" to "hundred meter per hour" The filling speed directly determines the molding ability and is also the most intuitive difference between the two.   Gravity casting: The molten metal slowly flows into the mold cavity along the sprue, and the filling speed is usually less than 1m/s. A medium-sized shell component, the filling process takes 3-10 seconds, and it is easy to cool and solidify halfway when encountering thin-walled structures, forming defects such as cold insulation and insufficient pouring. Pressure casting: The filling speed of the molten metal at the sprue can reach 30~70m/s, which is equivalent to a speed of about 108~252 kilometers per hour, equivalent to the operating speed of high-speed trains. For ordinary automotive motor housing and electronic control housing parts, it only takes 0.01~0.05 seconds from punch start to complete filling of the mold cavity, truly achieving millisecond level filling.   Due to its extremely fast speed, the metal liquid has already filled the entire mold cavity before it can cool and solidify. Therefore, die-casting can produce complex structures such as ultra-thin walls of 0.5mm, fine patterns, and micro buckles that cannot be formed by gravity casting.     3. Production efficiency: The difference in single cycle time can range from several times to tens of times The advantage of pressure and speed ultimately leads to a huge gap in production efficiency, which is also one of the core commercial values of die-casting.   Gravity casting: including the entire process of manual pouring, cooling and solidification, mold extraction, and cleaning of the sprue. The cycle time of a single part is generally 3-15 minutes per piece, and the daily production capacity of a single mold is only tens to hundreds of pieces. Cold chamber die casting (aluminum alloy): Fully automatic cycle production, with a single cycle time of about 60-120 seconds per medium-sized part, and a daily production capacity of thousands of pieces per equipment. Hot chamber die casting (zinc alloy small parts): The cycle speed is faster, and small precision parts can reach 10-30 seconds per piece. A single device can produce tens of thousands of pieces per day.   Converted, the production efficiency of die-casting is 10-50 times higher than that of gravity casting for the same part size. This is also the core reason why die-casting is almost preferred for large-scale production projects.

Die casting (pressure casting) and gravity casting are the two most commonly compared processes in the selection of non-ferrous metal parts such as aluminum alloys and zinc alloys. Many procurement and R&D personnel only know that "die-casting efficiency is higher and the finished product is more exquisite", but lack quantitative understanding of the core difference between the two - "high pressure and high speed": producing an aluminum alloy shell in a single cycle by gravity casting takes several minutes, while die-casting only takes a few tens of seconds; The same thin-walled structure is prone to cold insulation and material shortage in gravity casting, but can be formed in one go in die casting.   The core difference between gravity casting and pressure casting can be seen from their names - the driving force for filling is completely different, which is also the root of all performance differences.   Gravity casting (represented by metal mold gravity casting): Pour molten metal into the sprue, rely on the metal's own gravity to naturally flow into the mold cavity, slowly fill, naturally cool and solidify, with almost no additional external pressure throughout the process. Partial low-pressure casting will increase low-pressure assistance within 0.1MPa, but it still belongs to the category of gravity forming in essence.     Pressure casting (die casting): By applying mechanical pressure through injection punches, molten metal is pushed into the steel mold cavity at extremely high speeds, maintaining a high pressure of tens to hundreds of megapascals throughout the entire process until the casting is completely cooled and solidified. The core feature is high-pressure forced filling+high-speed filling+continuous pressure holding solidification.   Simply put, gravity casting is the process of "metal slowly flowing in on its own", while die casting is the process of "using high pressure to drive metal at high speed". The significant difference in driving forces directly leads to a full dimensional differentiation in efficiency, accuracy, and molding ability.

core strengths   Extremely high production efficiency and low unit cost: fully automatic cycle, single machine daily production can produce tens of thousands of pieces, and the cost-effectiveness of large-scale production far exceeds machining and sand casting;   Strong molding ability: capable of forming complex curved surfaces, buckles, reinforcing ribs, and micro threads in one piece, with a minimum wall thickness of 0.5mm, reducing the assembly process of parts;   High dimensional accuracy and smooth surface: tolerance can reach IT10~IT11, surface does not require polishing, can be directly sprayed or anodized;   High material utilization rate: The flow channel and material cake can be remelted in the furnace, with a material utilization rate of 85%~95%, far higher than CNC cutting processing;   Excellent comprehensive mechanical properties: high pressure dense structure, high strength and hardness, lightweight while meeting structural load-bearing requirements.   Inherent shortcomings   High initial investment: Die casting molds and large die casting machines are expensive and only suitable for large-scale production, with high single piece costs for small batches;   Easy to produce trace pores: High speed filling is prone to air entrapment, and ordinary die-casting parts cannot be welded at high temperatures; Vacuum die casting can significantly improve;   Material limitations: Only suitable for low melting point non-ferrous metals such as aluminum, zinc, magnesium, etc., unable to process steel and cast iron.     Mainstream application scenarios of die-casting   New energy vehicles: battery pack housing, motor end cover, electronic control housing, water-cooled heat dissipation chamber;   3C Electronics: Laptop frame, phone case, charger case, connector base;   Home appliance industry: air conditioning motor cases, washing machine weights, TV stands, kitchenware hardware;   General hardware: zinc alloy door lock accessories, bathroom hardware, small decorative shells;   Industrial equipment: gearbox housing, hydraulic valve body, instrument housing.

Many people wonder: gravity casting can also form, why does die-casting require a three-step combination of high pressure, high speed, and holding pressure? The three underlying logics determine the quality of castings.   1. High speed filling: solving the problem of thin-walled forming Aluminum alloy and zinc alloy have extremely fast cooling rates, and the metal liquid in the 0.5-1mm ultra thin wall area will solidify in a few seconds. Only high-speed filling at speeds above 30m/s can fill every detail of the mold cavity before the metal solidifies, avoiding material shortage, cold insulation, and grain defects.   2. High pressure boosting: eliminate shrinkage and increase density Metal cooling and solidification will cause volume shrinkage. Without external pressure filling, loose holes will form inside, leading to gas leakage and insufficient strength of the casting. Continuous compression under high pressure above 60MPa, with additional metal liquid to supplement the shrinkage gap, significantly reducing porosity and improving air tightness and mechanical strength.     3. Continuous pressure maintenance: stabilize grain structure During the pressure holding stage, the mold evenly dissipates heat, high-pressure suppresses grain coarsening, and the internal structure of the casting is dense and uniform. The tensile strength and hardness are much higher than those of ordinary gravity casting, meeting the mechanical requirements of automotive and new energy structural components.

1. Hot chamber die-casting machine (specialized for zinc alloy) structural principle The whole injection goose neck assembly is immersed in the molten metal inside the furnace, without the need for manual feeding; When the injection punch is pressed down, the molten metal in the furnace is automatically sucked into the injection chamber along the gooseneck tube, and then injected into the mold cavity at high pressure, circulating continuously. Complete workflow   Spray mold release agent and blow dry; Lock the mold tightly; The punch rises and the molten metal automatically flows into the gooseneck pressure chamber; High pressure injection with punch, high-speed filling of the mold cavity with molten metal; Pressure holding cooling solidification; Mold opening, ejection of castings, automatic cutting of material handle.   Core Features   Advantages: Short cycle time (15-30 times/minute), high degree of automation, less oxidation slag inclusion, suitable for small thin-walled parts; Limitations: Goose necks are soaked in high-temperature metals for a long time and can only be adapted to low melting point zinc alloys, unable to process high melting point materials such as aluminum alloys; Applicable: mobile phone decorative parts, hardware decorative shells, small precision connectors.   2. Cold chamber die-casting machine (mainstream aluminum/magnesium alloy) At present, the most commonly used model for large-scale industrial production is the complete separation of the furnace and injection chamber, which is a representative equipment for high-pressure die-casting. All new energy and automotive die-casting parts on the market use cold chamber technology. Complete working principle (7-step standard cycle)   Mold pretreatment: Preheat the mold to the process temperature using a mold warming machine, evenly spray water-based release agent with a robotic arm, blow dry the mold cavity, prevent casting from sticking to the mold, and control the cooling rate; Mold locking: The moving and fixed molds are completely closed, and the high-pressure locking mechanism is locked to resist the huge expansion force generated by the filling of the metal liquid and prevent flying edges; Quantitative feeding of soup: A robotic arm scoops a quantitative amount of molten aluminum liquid from an independent insulation furnace and pours it into a horizontal pressure chamber; Three stage injection (core high-pressure principle) Slow injection: The punch advances at low speed, smoothly pushing the molten metal to the gate, and expelling the air inside the chamber to avoid air entrapment; Fast injection: The punch instantly accelerates, and the molten metal rushes into the mold cavity at a speed of 30-70m/s, filling all thin-walled and complex structures within milliseconds; Boosting and pressure maintenance: At the moment when the mold cavity is filled, the punch applies a high pressure of 60-120 MPa and continuously compresses the casting; High pressure holding solidification: The pressure is continuously applied until the casting is completely cooled, offsetting the shrinkage and porosity caused by metal solidification shrinkage, and improving the density; Mold opening: The locking mechanism is released, the moving mold moves backwards, and the casting follows the moving mold to detach from the fixed mold; Pushing out parts: The ejector pin mechanism pushes out the casting, the mechanical arm picks up the parts, cuts off the material cake and flow channel, and enters the next cycle.     Core Features   Advantages: Suitable for high melting point aluminum alloys and magnesium alloys, capable of producing large shells and thick walled structures, with high casting strength and good sealing performance; Limitations: There is an additional scooping process, and the circulation speed is slower than that of the hot chamber machine (5-15 times/minute); Applicable: Automotive motor casing, battery pack casing, 3C frame, new energy electronic control casing, and large structural components of household appliances.

In the fields of automotive parts, 3C electronic casings, home appliance structural components, and new energy shell manufacturing, die-casting (high-pressure pressure casting, abbreviated as HPDC) is the core forming process for mass production of precision non-ferrous metal parts. Many procurement and product engineers only know that die-casting can produce complex thin-walled parts, but they are not clear about the underlying logic of high-pressure and high-speed filling, pressure holding and solidification. This often leads to unreasonable mold design and incorrect matching of process parameters, resulting in batch defects such as porosity, shrinkage, and deformation.   Die casting, also known as high-pressure pressure casting, is a near net forming metal manufacturing process that operates similarly to plastic injection molding. It involves instantly filling a steel precision mold cavity with molten liquid non-ferrous metal under high pressure (20-180MPa) and high speed (30-70m/s), maintaining pressure throughout the entire process until the metal is completely cooled and solidified. After opening the mold, it is ejected to obtain the finished casting.   Different from sand casting and gravity casting: gravity casting only relies on the self weight of the metal to fill the mold, with weak forming ability and low accuracy; Die casting relies on mechanical high-pressure forced filling, which can stably form 0.5mm ultra-thin walls, complex curved surfaces, small buckles, and micro threaded structures, with high dimensional accuracy and smooth surfaces. The subsequent machining volume is extremely small, making it the preferred process for large-scale precision parts.     Mainstream compatible alloys: aluminum alloy (ADC12, A380), zinc alloy (Zamak3/5), magnesium alloy, rarely used for high melting point metals such as steel. Die casting equipment is divided into two core types: hot chamber die casting machines and cold chamber die casting machines, which have completely different working principles and applicable alloys.

overflow trough Many people in the design of die-casting molds tend to overlook the overflow groove, thinking it is "redundant" and saving as much as possible, but in reality, they are completely wrong. The overflow groove is equivalent to the "cleaner" of the die-casting mold, mainly used to collect impurities, oxide scales, and gases generated during the filling process in the metal liquid, to prevent these impurities and gases from staying in the mold cavity, causing defects such as pores, slag inclusions, and shrinkage holes in the product.   The key to the design of overflow channels lies in their "position" and "size". The location is not selected correctly, impurities and gases cannot be discharged, which is equivalent to a white design; The size is too small to accommodate impurities and gases, and defects may still occur; The size is too large, which will waste raw materials and increase production costs.   Yurun designs overflow channels that accurately control two key points: firstly, the position is selected at the end of the metal liquid filling, the dead corners of the mold cavity, and places where gas is prone to gather, such as the corners of the parting surface and the thick walled parts of the product, to ensure precise collection of impurities and gases; Secondly, the size is determined based on the product size and the flow rate of the metal liquid. It should be able to accommodate impurities and gases while avoiding waste. At the same time, an exhaust channel should be designed to allow gases to be smoothly discharged from the mold.   And the overflow groove also needs to cooperate with the pouring system and the parting surface: the overflow groove should be close to the end of the gate, so that impurities and gases can be naturally pushed towards the overflow groove during the flow of the metal liquid. At the same time, the position of the overflow groove should be coordinated with the parting surface, which is convenient for subsequent demolding and trimming without additional processes.     cooling system   During the die-casting production process, the metal liquid is in a high-temperature state. After being injected into the mold cavity, it will bring a large amount of heat to the mold. If the mold temperature is too high, it will not only cause unstable product molding and shrinkage deformation, but also accelerate mold wear and aging, shorten the mold life; If the mold temperature is too low and the metal liquid cools too quickly, problems such as material shortage, cold insulation, and surface roughness may occur.   The cooling system is a magical tool for "cooling" the mold. Its core function is to control the temperature of the mold, keeping it within a stable and reasonable range, which can ensure the quality of product molding and extend the life of the mold. Many people design cooling systems and blindly increase the number of cooling water pipes, thinking that the faster the cooling, the better. However, this is not the case. Uneven cooling can cause mold deformation, which in turn affects product dimensional accuracy.   Yurun designs a cooling system that follows the principle of "uniform cooling and precise temperature control". Based on the shape and thickness of the product, the position and quantity of cooling water pipes are reasonably arranged to maintain consistent temperature in various parts of the mold, avoiding local overheating or undercooling. For example, in the thick walled areas of the product, the cooling water pipes should be arranged more densely to accelerate cooling; For thin-walled areas, the cooling water pipes can be sparser to avoid defects caused by rapid cooling.   At the same time, the cooling system also needs to coordinate with three other systems: the layout of the cooling water pipes should not affect the fit of the parting surface, the smoothness of the pouring system, or block the exhaust channel of the overflow groove. It is necessary to achieve uniform cooling without affecting the normal operation of other systems, ensuring stable product molding and longer mold life.

The parting surface is the "first threshold" of die-casting molds, and whether the demolding is smooth or not depends entirely on it The parting surface, commonly known as the "opening and closing surface" of a die-casting mold, is tightly adhered when the mold is closed, and the molten metal is formed inside the mold; When the mold is opened, separate it along the parting surface and take out the formed product. Seemingly just a simple contact surface, it is the first key threshold in the design of die-casting molds. If the design is not done well, there will be continuous troubles in the future.   Many beginners in designing parting surfaces only pursue "being able to fit and demold", but overlook two core issues: the position of the parting surface and the flatness of the parting surface. If the position of the parting surface is not selected correctly, the product is prone to sticking to the mold, scratching, and even burrs and flying edges during demolding. Additional rework and trimming will be required in the future; Uneven parting surface can cause material leakage during mold closing, which not only wastes raw materials but also damages the mold.   Yurun designs parting surfaces based on two core principles: first, try to choose the maximum contour of the product as much as possible, so that the force is evenly distributed during demolding, making it less likely to stick to the mold, scratch the product, and reduce burrs; Secondly, the parting surface should be flat and smooth, with a tight fit to avoid mold leakage. At the same time, the convenience of subsequent trimming should be considered to minimize trimming processes and reduce production costs.   In addition, the design of the parting surface also needs to be coordinated with the subsequent pouring system and overflow groove. For example, the position of the parting surface should be convenient for the smooth filling of the metal liquid, and at the same time, the overflow groove should be able to accurately collect impurities and gases, without neglecting one aspect. This is the first step in collaborative optimization.     The pouring system is the "channel" of molten metal, and whether it is filled smoothly or evenly is the key   The pouring system is the "channel" in the die-casting mold that allows the molten metal to enter the mold cavity from the injection chamber, which is equivalent to paving a "dedicated route" for the molten metal. The design of this route directly determines the speed and uniformity of metal liquid filling, which in turn affects the quality of product molding - filling too quickly can produce pores and splashes; If the filling is too slow, the metal liquid will cool down in advance, resulting in material shortage and shrinkage problems.   Many people design pouring systems and blindly increase the size of the sprue, thinking that this way the metal liquid can be filled faster, but this is not the case. The gate size is too large, and the impact force of the metal liquid is too strong, which will impact the mold cavity, shorten the mold life, and also produce pores; The gate size is too small, the filling speed is slow, and it is easy to have material shortage and cold insulation.   Yurun designs a pouring system that accurately calculates the gate size, runner length, and angle based on the size, shape, and material of the product. The core is "smooth, uniform, and stable". For example, for small thin-walled products, choose a finer gate, control the filling speed, and avoid splashing; For large thick walled products, the gate should be appropriately increased to ensure rapid filling of the metal liquid, while optimizing the shape of the flow channel to reduce resistance during the flow of the metal liquid and avoid uneven filling.   More importantly, the pouring system should cooperate with the parting surface and overflow groove: the position of the sprue should be aligned with the core area of the mold cavity, and at the same time, the metal liquid should be able to smoothly push gas and impurities towards the overflow groove during the flow process, avoiding gas being trapped in the mold cavity and causing porosity defects.

1. Reduce transmission error in the transmission chain   (1) Fewer transmission components, shorter transmission chain, and higher transmission accuracy;   (2) Adopting a reduced-speed transmission is an important principle for ensuring transmission accuracy, and the closer the transmission pair is to the end, the smaller its transmission ratio should be;   (3) The precision of the end components should be higher than that of other transmission components.   2. Reduce tool wear   (1) The tool must be re-sharpened before the tool size wear reaches the rapid wear stage   (2) Use dedicated cutting oil for sufficient lubrication   (3) The material of the cutting tool should meet the process requirements     3. Reducing the stress deformation of the process system   (1) Improve the rigidity of the system, especially the rigidity of the weak links in the process system;   (2) Reduce the load and its variations   4. Reduce thermal deformation of the process system   (1) Reduce heat generation and isolate heat sources   (2) Equilibrium temperature field   (3) Adopt reasonable machine tool component structure and assembly benchmark   (4) Accelerate to achieve heat transfer equilibrium   (5) Control the ambient temperature   5. Reduce residual stress   (1) Add a heat treatment process to eliminate internal stress;   (2) Reasonably arrange the technological process.   The above are methods to reduce errors in processing workpieces. Reasonable arrangement of processes can effectively improve the precision of the workpieces.

1. Adjust the process system   (1) Trial-cutting method involves the following steps: trial cutting, measuring the size, adjusting the depth of cut of the tool, cutting, and then trial cutting again. This process is repeated until the desired size is achieved. This method has low production efficiency and is mainly used for single-piece or small-batch production.   (2) The adjustment method obtains the required dimensions by pre-adjusting the relative positions of the machine tool, fixture, workpiece, and cutting tool. This method has high productivity and is mainly used for mass production.   II. Reducing machine tool errors   (1) The rotational accuracy of the bearing should be improved:   ① Select high-precision rolling bearings;   ② Adopt high-precision multi-oil wedge dynamic pressure bearings;   ③ Employ high-precision hydrostatic bearings   (2) Improve the precision of components compatible with bearings:   ① Improve the machining accuracy of the support holes in the box body and the spindle journal;   ② Improve the machining accuracy of the surface that mates with the bearing;   ③ Measure and adjust the radial runout range of the corresponding parts to compensate or offset the error.   (3) Apply appropriate preload to the rolling bearing:   ① It can eliminate gaps;   ② Increase the stiffness of the bearing;   ③ Homogenize the rolling element error.   (4) Ensure that the rotational accuracy of the spindle does not affect the workpiece

CNC programming is the most fundamental task in CNC machining. The quality of the workpiece machining program directly affects the final machining accuracy and efficiency of the machine tool. We can start by skillfully using inherent programs, reducing the cumulative error of the CNC system, and flexibly applying main programs and subprograms.   1. Flexible use of main programs and subprograms   In the processing of complex molds, it is generally adopted to use the form of multiple parts per mold. If there are several identical shapes on the mold, the relationship between the main program and subprograms should be flexibly utilized. The subprograms should be repeatedly called in the main program until the processing is completed. This not only ensures the consistency of the processing dimensions but also improves the processing efficiency.     2. Reduce the cumulative error of the numerical control system   Generally, incremental programming is used for machining workpieces, which is based on previous points for processing. Executing multiple program segments in succession will inevitably produce certain cumulative errors. Therefore, when programming, it is advisable to use absolute programming, so that each program segment is based on the workpiece origin. This can reduce the cumulative errors of the CNC system and ensure machining accuracy.   Machining accuracy is primarily used to describe the degree of product production. Both machining accuracy and machining error are terms used to evaluate the geometric parameters of the machined surface. However, the actual parameters obtained by any machining method are never absolutely accurate. From the perspective of the function of the part, as long as the machining error is within the tolerance range required by the part drawing, it is considered that the machining accuracy is ensured.

Magnesium alloy die casting is suitable for making thin-walled parts. Its material characteristics and die casting process adaptability can meet the needs of lightweight and complex forming of thin-walled parts, and it is widely used in fields such as 3C and automotive.   The characteristics of magnesium alloy material support the production of thin-walled parts. Magnesium alloy has a low density (1.8g/cm ³), only 2/3 of aluminum alloy. When making thin-walled parts, it can significantly reduce weight (about 30% lighter than thin-walled aluminum alloy parts of the same size), and is suitable for the lightweight requirements of 3C products (such as laptop casings and phone frames). Magnesium alloy has good fluidity in the molten state (15% -20% higher than aluminum alloy), and can quickly fill thin-walled cavities (with a small thickness of up to 0.5mm) during die casting. After forming, the structure is uniform, avoiding defects such as material shortage and cold insulation. It is suitable for making thin-walled parts with fine structures (such as buckles and grooves on thin-walled parts).     The types and thickness ranges of thin-walled components that are compatible are clear. The commonly used magnesium alloy die-casting thin-walled parts in the 3C field have a thickness of 0.5-2mm, such as the bottom shell of a 13 inch laptop (thickness 1.2-1.5mm) and the middle frame of a tablet (thickness 0.8-1.0mm). These thin-walled parts need to balance lightweight and structural strength. The tensile strength of magnesium alloy can reach 200-300MPa, which can meet the requirements of anti drop and anti deformation in daily use. Magnesium alloy die-casting thin-walled parts with a thickness of 1.5-3mm in the automotive field, such as car center control panel brackets (thickness 2.0-2.5mm) and motor end caps (thickness 2.5-3.0mm), can withstand slight vibrations around the engine while reducing weight.   Key process points ensure the quality of thin-walled components. High precision molds (processing accuracy ± 0.02mm) are required to produce thin-walled magnesium alloy die-casting parts, ensuring accurate cavity dimensions and avoiding uneven wall thickness (deviation should be controlled within ± 0.1mm). During die casting, it is necessary to control the injection speed (3-5m/s) and mold temperature (180-220 ℃). If the speed is too fast, it may cause burrs, and if it is too slow, it may lead to insufficient filling; Low temperature can affect the fluidity of magnesium alloys, while high temperature may cause mold sticking. After forming, deburring treatment (using laser or mechanical polishing) is required to ensure smooth edges of thin-walled parts and avoid scratching assembly personnel or other components with sharp parts.   Surface treatment enhances the durability of thin-walled components. The surface of magnesium alloy die-casting thin-walled parts is prone to oxidation and requires surface treatment, such as spraying (electrostatic spraying thickness of 30-50 μ m), anodizing (oxide film thickness of 5-10 μ m), to improve corrosion resistance (salt spray test can pass for 48-72 hours), and to adapt to humid environments (such as thin-walled parts of smart devices around bathrooms). Some thin-walled components (such as light luxury electronic accessories) can also be treated with wire drawing and sandblasting to enhance their appearance and texture.   Attention should be paid to adapting to scene limitations. Magnesium alloy die-casting thin-walled parts have limited temperature resistance (long-term use temperature ≤ 120 ℃) and are not suitable for scenarios near high-temperature sources (such as thin-walled parts near engine cylinder blocks). Thin walled components with high stress (such as load-bearing brackets) need to be reinforced with reinforcing ribs (width 0.8-1.2mm, height 2-3mm) to avoid deformation or fracture during use. When purchasing, it is necessary to clarify the usage scenarios and stress requirements of thin-walled parts with the manufacturer to ensure that the plan is compatible.

Aluminum alloy die-casting can produce large parts and can stably produce products such as box shells that require structural strength and dimensional accuracy, suitable for industrial, new energy and other fields.   Aluminum alloy material and process are suitable for the production of large parts. Aluminum alloy has strong rigidity (tensile strength 250-400MPa) and good corrosion resistance. When making large box shells, it can withstand external impacts (such as collisions during industrial equipment handling) and the weight of internal components (such as battery modules and circuit boards), and is not easily deformed. Aluminum alloy die-casting can be achieved through a large die-casting machine (locking force 1600T-6000T) to achieve one-time molding, avoiding the use of splicing technology for large box shells (reducing welding seams and improving sealing), such as new energy vehicle battery box shells (length 2-3m, width 1-1.5m). After one-time die-casting molding, the waterproof level can reach IP67, meeting outdoor use needs.     The size and performance parameters of the large box shell are clear. Common dimensions for aluminum alloy die-casting large box casings in the industrial field are: length 1-3m, width 0.8-2m, thickness 3-10mm, such as industrial control cabinet casings (length 1.5m, width 1m, thickness 5mm) and photovoltaic inverter casings (length 2m, width 1.2m, thickness 6mm). This type of casing requires reserved installation holes (aperture tolerance ± 0.1mm) and heat dissipation holes (size tolerance ± 0.2mm). The aluminum alloy die-casting accuracy can reach ± 0.05mm/m, which can meet the assembly requirements. The shell of the new energy vehicle battery case also needs to have anti extrusion performance (withstand extrusion force of ≥ 100kN without breaking). Aluminum alloy can improve its anti extrusion ability by adding silicon and magnesium elements (such as ADC12 aluminum alloy), which meets industry standards.   Process control ensures the quality of large box casings. Optimizing mold design is required for the production of large aluminum alloy die-casting box shells, using multi gate feeding (such as 3-5 gates) to ensure that the metal liquid evenly fills the large cavity (avoiding local material shortage); The mold needs to be equipped with an effective cooling system (such as a cooling water channel spacing of 50-80mm), controlling the molding temperature (mold temperature of 200-250 ℃, metal liquid temperature of 650-680 ℃), and reducing deformation of large parts caused by uneven cooling (deformation amount controlled within ≤ 2mm/m). After molding, X-ray inspection is required to check for internal bubbles (bubble diameter ≤ 0.5mm is qualified), in order to avoid cracking of the box shell caused by bubbles under stress.   Surface treatment is suitable for different usage environments. Large aluminum alloy die-casting enclosures for outdoor use, such as communication base station enclosures, require electrophoretic coating (paint film thickness of 20-30 μ m) or powder coating (coating thickness of 50-80 μ m). Salt spray testing can pass for 100-200 hours to prevent corrosion caused by rainwater and moisture. The casing of industrial workshops, such as machine tool distribution boxes, can be treated with anodizing to improve surface hardness (Hv ≥ 150) and prevent scratches caused by daily friction.   Clear adaptation scenarios and precautions. Aluminum alloy die-casting large box shells are suitable for mass production (minimum order quantity is usually 50-100 pieces), with a delivery cycle of 15-25 days (including mold debugging time). Due to the large volume of large items, customized packaging (such as wooden frames for fixation) is required during transportation to avoid collision and deformation during handling. When purchasing, a 3D drawing of the box shell (indicating dimensional tolerances, force points, and installation requirements) is required. The manufacturer will select the appropriate aluminum alloy material (such as ADC12, A380) and die-casting machine model according to the requirements to ensure that the product meets the standards.

During the die-casting process of aluminum alloy die castings, the mold temperature may be too low, the alloy liquid temperature may be too low, the filling speed may be too low, the release agent may be sprayed excessively or not dried, the gate design may be unreasonable, and the fast injection point setting may be unreasonable, all of which may cause cold insulation in the die castings.   The shape of the cold barrier is the shape of the initial liquid flow, with a single lubrication and rounded edges. Therefore, in radiographic images, it often appears as a smooth strip-shaped black line mirror with a relatively uniform width and lack of variation. The width of the line appears relatively large, and the blackness also changes in the width direction.     The area where aluminum alloy die castings exhibit cold insulation is usually located far from the sprue. It is because the metal flow is divided into several streams, and the flow front of each stream has already shown a condensation state. However, under the push of the metal flow at the back, it is still filled. When the metal flow that meets it also has a condensation front, the condensation layer that meets it cannot fuse anymore, and the joint presents a gap. The severe cold insulation has certain obstacles to the use of castings, which should be determined according to the conditions of casting use and the degree of cold insulation.

There are two types of peeling phenomenon in aluminum alloy die-casting parts: 1. Peeling after sandblasting or shot blasting. The parts with more cold lines on the surface of the product subjected to high-speed and high-pressure impact are prone to peeling. 2. After high-temperature baking, the product peels off. Due to high-temperature baking, there are many internal pores in some areas, and the release of internal air can easily cause surface bubbles or peeling. This can be solved through the following methods.   1. Firstly, improve the die-casting machine and die-casting parameters.   2. Adjust the die-casting speed and injection stroke, and increase the pressure.     3. Spray as little release agent as possible on this area to maintain thermal mold balance.   4. Improve from the aspects of mold design flow channel and exhaust.   The above are the reasons and solutions for peeling of aluminum alloy die-casting parts. After reading, I hope it will be helpful to you.

To produce high-quality zinc alloy die-casting parts, we must start with raw materials. So, what kind of problems can occur in zinc alloy die-casting parts due to poor materials?   1. If the composition of zinc alloy die-casting contains too many impurities, it will cause the casting to age and deform, manifested in volume expansion and easy cracking over time.   2. Poor quality materials for zinc alloy die-casting parts are not durable and prone to corrosion.     3. Not using high-quality zinc alloy for zinc alloy die-casting parts results in poor mechanical properties and insufficient tensile strength, which can easily lead to the fracture of zinc alloy die-casting parts.   4. Zinc alloy materials that have not passed environmental certification cannot undergo environmental testing.   Select high-quality zinc alloy die-casting raw materials, conduct strict screening, improve product quality from the source, and combine advanced equipment and technology to customize personalized zinc alloy die-casting parts for you, ensuring that every die-casting part delivered to customers is of high quality.

 Currently, aluminum alloys are widely used in various fields, and we can observe numerous aluminum alloy castings in the market. However, improper production processes or usage may lead to oxidation, typically manifesting as yellow spots and discoloration on the surface. Below, we will explore the oxidation phenomena that occur in aluminum alloy die-castings.      Since aluminum is inherently a reactive metal element, it tends to undergo chemical reactions in the air. Aluminum alloy castings, which are high-aluminum-content alloys, are processed by melting, resulting in tiny gaps between grains. Corrosive gases (including moisture containing carbon dioxide) can easily penetrate these gaps, leading to corrosion. After corrosion, aluminum oxide appears in powdered or fibrous forms, and the coloration of oxides from elements like copper in the alloy makes it look as if it has mold. Therefore, to address the oxidation phenomenon on the surface of aluminum alloy die-castings, Huayin Die-Casting employs specific measures for control, such as surface treatments, painting, and electrophoretic passivation, to prevent the occurrence of oxidation in aluminum alloy die-castings. Additionally, aluminum alloy die-castings should be stored in a dry and cool environment to minimize the risk of oxidation.     After understanding the causes of oxidation in aluminum alloy die-castings, you will no longer approach the resolution of such issues blindly

Die casting mold is one of the three major elements in die casting production. A mold with a correct and reasonable structure is a prerequisite for the smooth progress of die casting production, and plays an important role in ensuring the quality of die castings (lower machine qualification rate).   Due to the characteristics of die-casting technology, the correct selection of various process parameters is the determining factor for obtaining high-quality castings, and molds are the prerequisite for correctly selecting and adjusting various process parameters. Mold design is essentially a comprehensive reflection of various factors that may occur in die-casting production. If the mold design is reasonable, there will be fewer problems encountered in actual production, and the qualification rate of castings will be high. On the contrary, if the mold design is unreasonable, the wrapping force of the dynamic fixed mold is basically the same during the design of the die-casting parts, and the pouring system is mostly in the fixed mold and produced on the Guannan die-casting machine where the punch cannot be fed after injection, it cannot be produced normally, and the castings are stuck to the fixed mold all the time.     Although the surface finish of the fixed mold cavity is very smooth, there is still a phenomenon of sticking to the fixed mold due to the deep cavity. Therefore, in mold design, it is necessary to comprehensively analyze the structure of the casting, familiarize oneself with the operation process of the die-casting machine, have the possibility of adjusting the die-casting machine and process parameters, master the filling characteristics in different situations, and consider the methods of mold processing, drilling and fixing forms before designing a mold that is practical and meets production requirements.   Due to the extremely short filling time of the metal liquid, the specific pressure and flow rate of the metal liquid are very high, which makes the working conditions of the die-casting mold extremely harsh. In addition, the impact of alternating stress caused by rapid cooling and heating has a significant impact on the service life of the mold.   The service life of a mold usually refers to the natural damage that occurs through careful design and manufacturing, combined with good maintenance and upkeep, under normal use conditions, and before it can be repaired and scrapped, the modulus of the die cast (including the number of waste products in die casting production).   In actual production, there are three main forms of mold failure: ① thermal fatigue cracking damage failure; ② Fragmentation failure; ③ Corrosion failure.

1、 The importance of copper in mold processing In mold processing, there are many methods used for mold processing, such as milling machine processing, grinding machine processing, wire cutting processing, lathe processing, and discharge machining with spark machines. Copper rod is an electrode used in spark machine discharge machining. The spark machine discharge machining using copper rod as an electrode is mainly used for the cavity machining of molds, which is the core and key part of the mold.     2、 Next, let's talk about the importance of copper in mold processing, from the following aspects:   1. The processing blind spots of common processing methods require the surface shape of the mold cavity to be exactly the same as the shape of the product itself, which is also a basic requirement for mold processing. The most commonly used processing methods in mold processing are three-axis milling machines, machining centers, engraving processing, and wire cutting. Firstly, let's talk about three similar machining methods: three-axis vertical milling machine, machining center, and engraving machining. The biggest difference between them lies in some differences in control and driving methods. The key similarity is that they all use cutting tools for force processing. Due to the effect of force, considering the strength of the cutting tool, the ratio of tool diameter to blade length is limited. In actual machining, if the depth needs to be machined, the diameter of the tool must be relatively large. For small areas that need to be machined, the tool cannot be too long. This situation is very common in actual product modeling, such as machining some sharp corners and narrow and deep small areas. Although wire cutting can solve the problem of sharp corners, it can only process through holes, and if it is a blind hole, it is powerless.   2. The hardness of mold materials is due to the special requirements of the product material or the product itself. Some mold materials have high hardness, even close to the hardness of cutting tools. For such mold materials, if they are directly processed with cutting tools, it will inevitably cause rapid wear and tear of the processing tools, and the surface quality is difficult to meet the requirements. Therefore, if such materials are directly processed, they will not meet the requirements in terms of processing quality and efficiency   3. The hardness of the material has no effect on electrical discharge machining. Using copper as an electrode for mold machining belongs to electrical discharge machining. In electrical discharge machining, the hardness of the processed material has no effect on electrical discharge machining. This is one of the advantages of copper machining, which precisely solves the problem in Article 2.   4. The cutting performance of materials used for processing copper bars is usually purple copper, which is a relatively soft material with good ductility. In actual processing, the cutting performance is much easier than directly processing steel, which is one of the advantages of copper bar processing and solves the problem in the second point.   5. The flexibility of copper wire itself is different from that of molds. For molds, a certain part of the product's shape can only be completely processed on a certain piece of material, regardless of the difficulty of processing. If only one copper wire is processed for a product, there may be blind spots or difficult to process areas. The blind spots and difficult to process parts can be decomposed into several copper wires that are easy to process, as long as these parts can be pieced together to fully include the product's shape. In this way, the problem in the first point is solved, which is also one of the important key factors in the existence of copper.

When the aluminum alloy die-casting mold is out of service, it is necessary to regularly inspect, organize, and protect it in order to reasonably extend the service life of the die-casting mold. So, how to maintain the aluminum alloy die-casting mold for permanent aluminum alloy die-casting? After the aluminum alloy die-casting mold is removed, the aluminum die-casting engineer will lift it to the designated position and place it. The die-casting mold equipment maintenance worker will carry out the following protective maintenance.   1. Clean the die-casting mold (including guide rail slider, concave mold, core, exhaust system, etc.) to ensure smooth mold sorting and exhaust pipe.     2. Clean the oil stains on the mold and cooling circulation water pipe.   3. Repair or replace cores and small chains with bends, cracks, and fissures.   4. After the relevant personnel clarified the repair plan for the damaged die-casting mold, the die-casting mold maintenance personnel immediately carried out repairs. The repaired die-casting mold must be inspected by relevant personnel and confirmed to be qualified before the hydrostatic test can be carried out.   5. The maintenance of die-casting equipment must inspect the aluminum alloy die-casting molds on time and keep records. When repairing or replacing the core, records should also be kept. To achieve better quality and longer service life of aluminum alloy die-casting molds, it is necessary to organize, inspect, protect and maintain the molds in a comprehensive manner. Yurun has also done a thorough job in these aspects.   With the development of the economy, the production value of stainless steel plates in China now accounts for over 50% of the country's total. Due to the influence of high-tech, zinc alloy materials continue to be improved, addressing the shortcomings of previous products and occupying a key position in the sales market. Therefore, more and more customers choose to use zinc alloy die-casting products. So what are the advantages of aluminum alloy die-casting parts?   1： Accuracy The standard precision, surface precision, and thick walled casting precision of aluminum alloy die-casting parts are all very high. The products produced and manufactured have detailed lubrication, glossy white color, and are suitable for the requirements of glossy products. The product has a stable appearance, strong conversion ability, and is suitable for various production requirements.   2： Mass production capability The equipment has high production efficiency, and some aluminum alloy die-casting parts can be die cast a thousand times every eight hours, with a long service life. Some lifespans can reach tens of millions or even millions of times.   3： Rationality Due to the advantages of surface lubrication without sand holes on aluminum alloy die-casting parts, they can be used directly without production and processing, saving some process flow and resulting in very low output value. Due to his continued increase in usage and reduction in labor, the price of castings is also very cheap.