在考虑锻造工艺时特别是后一火的锻造时，应尽量避免在临界变形程度下进行，以免得到粗大晶粒***。具体来说，高温下金属塑性好，变形抗力小，应采用远大于临界变形程度的较大变形量锻造；低温修正时采用低于临界变形程度的小变形量进行局部修整。

When the forging process is cidered, especially when the last fire is forged, the critical deformation should be ***oided as far as , so as to ***oid coarse grain structure. Concretely speaking, high temperature metal has good plasticity and ***all deformation resistance. We should adopt large deformation amount forging far greater than critical deformation degree. When low temperature correction is used, ***all deformation below critical deformation degree should be used for local trimming.

不知道听到工艺两个字的时候我们更多的想到的是什么?我想很多人对工艺的追求大多体现在对一些艺术品上面。其实不仅仅是艺术品对工艺的要求非常高。碾环是指通过专用设备碾环机生产不同直径的环形零件，主要用来生产汽车轮毂、火车车轮等轮形零件。在我们的机械领域对工艺也是精益求精的，因为只有高超的工艺才能制造出更的产品，就比如说大口径法兰对它的工艺要求也是很高的。

I don't know what we think about more when we hear the two of the craft?生产中使用的锻锤有空气锤和蒸汽-空气锤，有些厂还使用结构简单，***少的弹簧锤、夹板锤、杠杆锤和钢丝锤等。 I think a lot of people's pursuit of the craft is mostly on some of the works of art. In fact, not only is the art of art demanding very high technology. In our field of machinery, we also strive for improvement in technology, because only superb technology can make more perfect products, for example, large diameter flanges require high technological requirements for them.

镦粗是镦粗示意图使毛坯高度减小，横断面积增大的锻造工序。 镦粗工序主要用于锻造齿轮坯、圆饼类锻件。镦粗工序可以有效地改善坯料***，减小力学性能的异向性。 镦粗与拔长的反复进行，可以改善高合金工具钢中碳化物的形态和分布状态。

Upsetting is the forging process that indicates that the blank height is reduced and the cross section area is increased. The upsetting process is mainly used for forging gear blanks and round cake forgings. The upsetting process can effectively improve the billet structure and reduce the anisotropy of mechanical properties. The morphology and distribution of carbides in high alloy tool steel can be improved by repeated upsetting and drawing.