模具零件在锻造过程中由于锻造工艺不当常常会产生很多缺陷,如大晶粒、晶粒不匀、裂纹、折叠、偏析、位错、流线分布不顺等。其中折叠是最常见的内患之一,它不仅减小了零件的承载面积,而且工作时折叠处会产生应力集中形成疲劳源。因此,技术条件中规定锻件上一般不允许有折叠。 Mold parts in the forging process due to improper forging process often have many defects, such as large grains, grain unevenness, cracks, folding, segregation, dislocation, streamline distribution and so on. Folding is one of the most common internal problems, which not only reduces the bearing area of ​​the parts, but also creates stress concentration in the folded area to form a fatigue source. Therefore, the provisions of the technical conditions forgings generally do not allow folding.