二十世纪的工艺技术虽然发展迅速,但直到六十年代为止,大部分的制造工艺还是依靠技木工人的熟练程度和直觉来提高铸造、冲压成形和机床加工的质量。当前的科学研究已为制造业开辟了新的途径,用以减少在工艺上对调整试验的依赖,并提高了生产能力。有些新材料具有强度高,耐久和重量轻的特点,但在成形和加工过程中必须有严密的控制。例如用某一新钢种来取代加工性能良好的低碳钢时,发现前者在冲压成形时容易破裂。这是一个难处理的问题,所以需要掌握压力成形过程中材料的变化情况。 Twentieth-century technology, though rapidly evolving, was not until the 1960s that most of the manufacturing processes relied on skilled and intuitive craftsmanship to improve the quality of foundry, stamping and machining. Current scientific research has opened up new avenues for manufacturing to reduce the reliance on process adjustments in manufacturing processes and increase productivity. Some new materials have the characteristics of high strength, durability and light weight, but they must be tightly controlled during forming and processing. For example, with a new type of steel to replace the good machinability of low-carbon steel, the former found in the stamping easily rupture. This is a difficult problem to deal with, so we need to know the material changes during pressure forming.