Aluminum alloy die-casting may encounter various common problems during the production process. Here are some common problems and their solutions: Stomata (bubbles): Problem description: Porosity appears on the surface or inside the aluminum alloy casting, affecting the appearance and performance. solution: Avoid gas trapping and accumulation by optimizing mold design and process parameters. Use a suitable pouring system to increase metal filling speed and reduce gas inclusions. Add an appropriate amount of gas eliminator or improve the degassing treatment of metal. Thermal cracks: Problem Description: Cracks appear in aluminum alloy castings during the cooling process, affecting their mechanical properties. solution: Control the casting temperature and cooling rate to avoid thermal stress caused by rapid cooling. Use preheated molds or preheated metal materials to reduce thermal stress. Optimize the metal composition and alloy ratio to reduce the tendency of metal to crack. Cold cracking (cold cracking): Problem Description: Cracks appear in aluminum alloy castings after cooling, usually in thin-walled parts or corners. solution: Design appropriate relaxation angles and edge chamfers to reduce stress concentration. Use appropriate annealing or aging treatments to reduce tissue stress. Optimize mold design to reduce stress caused by uneven mold shrinkage. Size deviation: Problem description: The dimensions of aluminum alloy castings do not match the design requirements. solution: Control the metal pouring temperature and cooling rate to reduce metal shrinkage. Use appropriate mold materials and cooling systems to reduce the impact of mold deformation on dimensions. Regularly inspect and maintain molds to maintain mold accuracy and stability. Surface defects: Problem description: Defects such as oxidation, pores or inclusions appear on the surface of aluminum alloy castings. solution: Optimize mold surface treatment and spray coating to improve surface finish and oxidation resistance. Control pouring speed and temperature to reduce metal oxidation and gas inclusions. Strengthen the mold ventilation and cooling system to reduce the temperature gradient on the mold surface and avoid the formation of surface defects. The above are some common aluminum alloy die-casting problems and their solutions. In actual production, comprehensive analysis and processing are required based on specific circumstances.

Typically, die casting machines are not suitable for direct die casting of stainless steel. This is because stainless steel usually has a higher melting point and liquid viscosity, as well as a higher solidification shrinkage. These characteristics make the die-casting process of stainless steel relatively difficult. Although stainless steel generally has a higher melting point, there are specialized high-pressure casting equipment and processes that can be used to cast stainless steel parts. These equipment and processes are often able to provide sufficient pressure and temperature to melt the stainless steel and inject it into the mold. However, these equipment and processes are costly and require strict process control and equipment maintenance. Therefore, in general, die casting machines are more suitable for casting low melting point metals, such as aluminum alloys, magnesium alloys, zinc alloys, etc. For high melting point metals such as stainless steel, other processing methods are usually used, such as sand casting, investment casting, etc.

Die-casting molds can be divided into various categories according to their structure and use. The following are common classifications of die-casting molds: Classification by structure: Cold Chamber Die: Suitable for casting high melting point metals, such as aluminum alloys, copper alloys, etc. In a cold chamber die casting machine, molten metal is fed through a nozzle into the mold cavity to be cast. Hot Chamber Die: Suitable for casting low melting point metals, such as zinc alloy, magnesium alloy, etc. In a hot chamber die casting machine, the mold is partially immersed in molten metal, which is pushed into the mold cavity by a plunger. Classified by use: Stamping die (Trim Die): A die used to cut the shape of a die casting to the final size. Hydraulic Die: A mold used to apply hydraulic pressure during the die casting process to form die castings. Injection Die: A mold used to inject molten metal during the die casting process. Classified by shape and function: Single Cavity Die: A mold that can only produce one part at a time. Multiple Cavity Die: A mold that can produce multiple identical or different parts at one time. Runner Die: A mold used to control the path and speed of metal liquid flowing into the mold. Core Pull Die: A mold used to extract parts with complex internal structures during the die casting process. These classifications are only common classifications. In actual applications, die-casting molds may be customized and combined according to different production requirements.

Stamping: Stamping is a process in which a sheet of metal is placed in a mold and then deformed into the desired shape through impact or pressure. In the stamping process, a stamping machine and a die are usually used, and the die presses the metal sheet into the desired shape, such as flat, curved, convex or concave, etc. Stamping is suitable for producing large quantities of sheet metal parts, such as automobile body parts, household appliance casings, etc. Casting: Casting is a process in which molten metal is poured into a mold and solidified to obtain the desired shape. In the casting process, a metal mold or sand mold is usually used, and molten metal is injected into the mold. After the metal cools and solidifies, the mold is opened to obtain the casting. Casting is suitable for producing large, complex-shaped parts, such as engine blocks, mechanical parts, etc. In general, stamping is suitable for the production of thin sheet metal parts and high-volume production, while casting is suitable for the production of large, complex-shaped parts and single-piece production.

Cold shut in die castings refers to defects caused by the solidification of metal liquid in certain parts or areas due to the excessive cooling rate in certain parts or areas when the metal liquid fills the mold during the filling process. This affects the sealing, strength and appearance of the part. The following are some common causes of cold shut problems in die castings and their corresponding solutions:   1. Mold design issues: Cause of the problem: The mold structure design is unreasonable, resulting in uneven cooling speed of the metal liquid during the filling process. Solution: Optimize the mold design, add a cooling system, adjust the mold structure to improve the fluidity of the metal liquid in the mold, ensure uniform filling of the metal liquid and avoid excessive cooling speed.   2. Improper temperature control of metal liquid: Cause of the problem: The temperature of the metal liquid is too high or too low, which may lead to uneven cooling speed and the formation of cold insulation. Solution: Strictly control the pouring temperature of the metal liquid to ensure pouring within a suitable temperature range to avoid excessive temperature gradients.   3. Gating system design issues: Cause of the problem: The design of the pouring system is unreasonable. If the pouring port is improperly designed or positioned inappropriately, it may cause the metal liquid to form a cold seal during the filling process. Solution: Optimize the design of the pouring system, adjust the position and shape of the pouring opening, increase the pouring opening or change the pouring direction to promote the flow and filling of metal.   4. Composition and solidification of metal alloys: Cause of the problem: The composition of the metal alloy is uneven or the solidification is poor, which may cause the metal liquid to solidify unevenly during the filling process, forming a cold seal. Solution: Optimize the formula of the metal alloy, strengthen the mixing and homogenization of the metal liquid, and ensure the solidification and fluidity of the metal liquid.   5. Improper operation: Cause of the problem: Improper control by the operator during the die-casting process, such as excessive pressure, temperature or speed, may also cause the metal liquid to form a cold seal during the filling process. Solution: Train operators to ensure they understand and correctly implement operating procedures, strictly control die-casting parameters, and avoid operating errors. Through the above measures, cold shut problems in die castings can be effectively prevented and reduced, and the quality and reliability of die castings can be improved.

Shrinkage cavities (also known as sinkage) in die castings are a common defect that usually occurs in thick-walled or densely populated areas of the part. Such defects may affect the mechanical properties and appearance of the part. The following are some common causes of shrinkage cavities in die castings and their corresponding solutions:   1.Insufficient filling of metal liquid: Cause of the problem: The metal liquid failed to completely fill the mold cavity during the filling process, causing shrinkage cavities to form in some areas. Solution: Adjust the pouring system and pouring parameters, increase the pouring opening or change the pouring direction to promote metal filling and improve the filling rate and fullness.   2. Mold design issues: Cause of the problem: Improper mold design, such as an overly thick or overly complex structure, may cause the metal liquid to be hindered during the filling process and form shrinkage cavities. Solution: Optimize the mold design, reduce the thick-walled parts of the part, add ventilation holes or improve the gating system to promote the filling and flow of metal liquid.   3. Improper temperature control of metal liquid: Cause of the problem: If the temperature of the metal liquid is too high or too low, it may cause poor fluidity of the metal liquid during the filling process and easily form shrinkage cavities. Solution: Strictly control the pouring temperature of the metal liquid to ensure that it is poured within a suitable temperature range and avoid the temperature being too high or too low.   4. Organizational structure issues of metal alloys: Cause of the problem: The chemical composition of the metal alloy is uneven or there are other impurities, which may cause the metal liquid to solidify unevenly during the filling process and form shrinkage cavities. Solution: Optimize the formula of metal alloys, strengthen the stirring and homogenization of metal liquids, and ensure that the organizational structure of metal alloys is uniform and stable.   5. Improper operation: Cause of the problem: Improper control by the operator during the die-casting process, such as excessive pressure, temperature or speed, may also cause the metal liquid to form shrinkage cavities during the filling process. Solution: Train operators to ensure they understand and correctly implement operating procedures, strictly control die-casting parameters, and avoid operating errors. Through the above measures, shrinkage cavities in die castings can be effectively prevented and reduced, and the quality and reliability of die castings can be improved.  

During the manufacturing process of die castings, pitting (also called pitting) is a common surface defect that affects the appearance and quality of the part. Pockmarks usually appear as many small bumps or depressions on the surface, similar to pitting. The following are some common causes of pitting problems in die castings and their corresponding solutions:   1. Gases and bubbles of metallic liquid: Cause of the problem: The gas and bubbles in the metal liquid were not completely eliminated during the filling process, resulting in pitting on the surface of the die casting. Solution: Optimize the treatment process of the metal liquid, take measures such as vacuum evacuation or inert gas treatment to reduce the gas content, optimize the pouring system and pouring parameters to ensure that the filling of the metal liquid is uniform and stable, and reduce gas trapping.   2. Improper temperature control of metal liquid: Cause of the problem: If the temperature of the metal liquid is too high or too low, it may lead to poor fluidity of the metal liquid during the filling process, and it is easy to form pits. Solution: Strictly control the pouring temperature of the metal liquid to ensure that it is poured within a suitable temperature range and avoid the temperature being too high or too low.   3. Mold surface problems: Cause of the problem: There are problems such as wear, oxidation or contamination on the mold surface, which causes the metal liquid to easily flow unevenly during the pouring process and form pitted surfaces. Solution: Clean and maintain the mold regularly to ensure the mold surface is smooth and clean, and use appropriate coatings or paints to prevent oxidation or contamination of the mold surface.   4. The flow of metal liquid is not smooth: Cause of the problem: The metal liquid is hindered or flows unevenly during the filling process, resulting in insufficient filling and prone to pitting. Solution: Optimize the design of the pouring system, reduce the resistance of the metal liquid during the flow process, increase the pouring port or change the pouring direction to promote the flow of metal.   Longhua has extensive experience in the field of designing high-precision molds, which can effectively prevent and reduce pitting problems in die castings and improve the surface quality and appearance of die castings.  

Porosity and bubbles in die castings are common quality issues that can affect the sealing, strength and appearance of the part. Here are some common causes and solutions for blowhole and bubble problems: 1.Gases and bubbles in metallic liquids: Cause of the problem: There may be gas absorption or moisture absorption in the metal liquid, as well as gas released during the dissolution or cooling process of the metal. These gases cannot be completely discharged during the die casting process and form pores and bubbles. Solution: Use high-quality metal alloys, treat the metal liquid with vacuum or inert gas to reduce gas content, use appropriate pouring systems and pouring speeds, and optimize die-casting parameters to reduce gas entrapment. 2.Mold surface oxidation or contamination: Cause of the problem: Oxidation or contaminants on the mold surface may be carried into the die casting as the metal flows into the mold, forming bubbles. Solution: Clean and maintain the mold regularly, use surface coatings or paints to prevent oxidation, and ensure the mold surface is smooth and clean. 3.The flow of metallic liquid is not smooth: Cause of the problem: The metal liquid is obstructed or flows unevenly during the filling process, causing gas to be entrained into the die casting. Solution: Optimize the design of the pouring system, reduce the resistance of the metal liquid during the flow process, increase the pouring port or change the pouring direction to promote the flow of metal. 4.Improper temperature control of metal liquids: Cause of the problem: The temperature of the metal liquid is too high or too low, which may lead to the formation of bubbles. Solution: Control the temperature of the metal liquid to ensure that the metal liquid is within an appropriate temperature range to reduce the dissolution and release of gas. 5.Die casting parameters are inappropriate: Cause of the problem: Incorrect die-casting parameter settings, such as pressure, speed, etc., may cause voids and pores in the metal liquid during the filling process. Solution: According to the specific die-casting requirements and metal properties, optimize the die-casting parameters to ensure that the metal liquid is filled evenly and stably. Longhua has extensive experience in the field of designing high-precision molds, which can effectively prevent and reduce cracks in die-casting parts and improve the quality and reliability of die-casting parts.