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铸造及锻造早为人们所知,在生产中各具有其优点。砂型铸造通常可用低费用的熔融金属开始在单道工序里铸成极复什形状的零件,而锻造的毛坯是用可锻材料的预制件,锻造成形状较简单而尺寸精度高、表面光滑及机械性能高的零件。另一方面,传统的锻造经常要求几组模具把棒材或其他已具一定形状的零件锻成可供机加工的零件。而且可锻预制件的费用比用于铸造的熔融金属贵得多。铸造件的缺陷是比锻造件强度低,表面粗糙。混合两种工艺的优点和减少它们的缺陷,这样就导致了挤压铸造的发展——这是一种混合工艺,它将熔融金属挤压成“锻件”以供进一步机加工。
Casting and forging have long been known and have their advantages in production. Sand casting usually begins with a low-cost molten metal casting a very complex shape of the parts in a single pass, while the forging blank is made of pre-fabricated forgable material with a simple shape and high dimensional accuracy, with a smooth surface and High mechanical properties of the parts. On the other hand, traditional forging often requires that several sets of molds be used to forge bar or other shaped parts into machined parts. And forging preforms costs more than the molten metal used for casting. Castings defects than forging strength, surface roughness. The advantages of mixing both processes and reducing their defects have led to the development of extrusion casting - a hybrid process that extrudes molten metal into “forgings” for further machining.