Aluminum low-pressure casting is an advanced casting process,
which requires strict control from multiple aspects in controlling the quality of castings.
First of all, the quality of raw materials is crucial. Select high-quality aluminum ingots to ensure that their chemical composition meets the standards and the impurity content is low to ensure the basic performance of the castings. During the smelting process, the process parameters such as smelting temperature, time and stirring should be strictly controlled to make the alloy fully melted and uniform, and avoid the generation of defects such as slag inclusions and pores.
Secondly, the design and manufacture of the mold also have a great influence on the quality of the casting. The mold should have good thermal conductivity, sufficient strength and rigidity, as well as the size and shape. Reasonable runner system design can ensure the smooth flow of molten metal, avoid problems such as sand blasting and turbulence, and reduce defects such as stress and shrinkage cavities inside the casting.
Furthermore, the control of low-pressure parameters during the casting process is the key. Parameters such as the size of the low pressure, filling speed and holding time should be reasonably adjusted according to factors such as the structure, size and material of the casting. Too low a pressure may result in incomplete filling of the molten metal, while too high a pressure may cause molten metal splashing or mold deformation. The filling speed should be moderate. Too fast a pressure may easily cause turbulence and air entrainment, while too slow a pressure may cause defects such as cold shut. The holding time should be long enough to ensure that the casting is fully compensated for shrinkage and reduce shrinkage cavities and shrinkage.
Afterwards, the post-processing of the casting should not be ignored. It includes cleaning, heat treatment and other processes. Cleaning can remove impurities and burrs on the surface of the casting and improve the surface quality; heat treatment can improve the mechanical properties and metallographic structure of the casting and improve the quality stability of the casting.
Details: The raw materials must be high-quality aluminum ingots (low impurity content and chemical composition up to standard). The temperature (700-750℃), time and stirring process must be controlled during smelting to avoid slag inclusions and pores. The mold design must take into account thermal conductivity (thermal conductivity ≥150W/m·K), strength and dimensional accuracy. The optimization of the runner system can reduce sand blasting and turbulence and reduce internal stress (residual stress ≤50MPa). Among the process parameters, low pressure (0.02-0.06MPa), filling speed (10-20cm/s) and holding time (30-60s) need to be dynamically adjusted according to the casting structure to avoid cold shut or shrinkage defects. The post-processing stage improves the mechanical properties and stability through cleaning (surface roughness Ra≤3.2μm) and heat treatment (T6 aging hardness ≥80HB). In short, only by strictly controlling the raw materials, molds, casting process parameters and post-processing can the quality of aluminum low-pressure castings be effectively improved and high-quality castings that meet the requirements be produced.
If you have a large-scale production demand for aluminum die-castings, you can choose to cooperate with Mulan Metal. Mulan Metal has 12 years of OEM aluminum die-casting production experience and has helped customers in more than 30 countries complete the processing of aluminum die-castings. And it has been unanimously affirmed. Looking forward to your cooperation consultation.
Here is our Custom Aluminum die castings Display：
