In view of the fact that the spheroidizing structure of the cold working die steel supplied by the metallurgical plant should be qualified, the carbide net should be basically eliminated, and the carbide segregation degree of the high alloy stainless steel should also be regulated. Therefore, not all tool steels must be re forged in the factory.

在一定的条件下．采用轧制的型材直接加工产品是合理的。尽管如此．在制造厂需要改锻的工具钢仍然占相当大的比重。除了热锻成形可以减少切削加工和充分利用钢材等原因之外，冷作模具钢的改锻有利于提高钢材的内在质量，作用大致有以下几方面。

Under certain conditions, it is reasonable to use rolled profiles to process products directly. In spite of this, the tool steels which need to be forged still account for a considerable proportion. In addition to hot forging can reduce cutting processing and make full use of steel and other reasons, tool steel forging is conducive to improve the internal quality of steel, the role of roughly the following aspects.

1)—般说来，钢材的截面愈小，锻造比愈大，冶金质量本身就愈好。出此凡是需要先经过改缎再坦行加上的工具毛坯，席尽可能选用较小截面的钢材改锻为较大截向的毛坯，这样有利于保证工具钢内部有较好的冶金质量。

1) Generally speaking, the smaller the steel section and the larger the forging ratio, the better the metallurgical quality itself. For the tool blanks that need to be changed to Satin first and then put on smoothly, the steel with smaller cross-section shall be used as far as possible, and the blank with larger cross-section shall be forged as far as possible, which is conducive to ensuring better metallurgical quality of tool steel.

2)改锻使工具钢内部的流线分布比较合理。例如盘形铣刀如果用略大于具外径的钢材落料后直接进行机械加工，从钢材利用率和降低加工成本方面考虑是合理的，然而钢内央杂物排列的方向、碳化物偏析的排列方向都和切削刃口平行，即处于的受力方向，对使用性能不利c如果用小规格的俐材经过改锻

2) The reasonable distribution of the tool steel makes the inner part of the tool more reasonable. For example, if the disc milling cutter uses steel with a slightly larger outer diameter for direct machining after blanking, it is reasonable to consider the steel utilization rate and reduce the processing cost. However, the arrangement direction of the impurities in the steel and the carbide segregation direction are parallel to the cutting edge, that is, they are in the maximum stress direction, which is unfavorable to the service performance

(镦粗后打扁)，则流线呈放射状(径向)分布，改善了铣刀的性能.

(flattening after upsetting), the streamline is radial (radial) distribution, which improves the performance of milling cutter

3)通过改锻商可能改善关键部位的材质，使上具受力严重的部他的材质获得改善，从而收到大幅度提高工具钢寿命的效果。

3) It is possible to improve the material of the key parts by changing the forging mill, so that the material of the part with the most severe stress can be improved, so that the life of tool steel can be greatly improved.

4)锻造的加热过程想着扩散退火的作用。工具钢改锻时的加热温度可以略高于钢锭开坏的加热温度，因为在开坯和轧制之后，品内和品问偏析己明显改善。钢材改银加热时局部熔化的倾向减小。加热温度愈高，保温时刘愈长，偏析酌作用愈显著。显然模具钢在高温加热的过程市奥氏体晶粒长大，似在高温加

4) The effect of diffusion annealing is considered in the heating process of forging. After heating, the temperature of the ingot and the hot rolled steel can be improved slightly. When the steel is changed to silver, the tendency of local melting decreases. The higher the heating temperature is, the longer the holding time is, and the more obvious the effect of eliminating segregation is. It is obvious that austenite grains grow up in the process of die steel heating at high temperature

热后紧接着进行压力加工，则可以细化英氏体晶粒，如果终锻温度控制得好、锻后冷却方式合理，则可以抑制网状碳化物的出现，达对于保证钢的RJ加工性和终的使用件能都十分重要，因此工具钢的终锻温度贩予以控制，一般应控制在表3．2的范围内。

If the final forging temperature is well controlled and the cooling method after forging is reasonable, the appearance of network carbide can be restrained, which is very important to ensure the RJ workability of the steel and the final performance of the used parts. Therefore, the final forging temperature of the tool steel should be controlled within the scope of table 3.2.