The following factors should be considered in the material selection of cold deformation die:

1)模具的工作条件，包括设备种类、加工频率、被加工的材质、润滑及环境等；

1) Working conditions of the mold, including equipment type, processing frequency, processed material, lubrication and environment, etc;

2)模具形态的复杂程度及加工程序；

2) The complexity of mold shape and processing procedure;

3)产品的生产批量及技术要求；

3) Production batch and technical requirements of products;

4)模具材料来源的难易及加工条件，大型模具的材料费用往往占模具成本的50%以上，对于形态复杂、精度要求高的模具，宜选用淬火变形小的模具钢。

4) Due to the difficulty of mold material source and processing conditions, the material cost of large molds often accounts for more than 50% of the mold cost. For molds with complex shape and high precision requirements, die steel with small quenching deformation should be selected.

根据实际使用，常用的冷变形模具钢有低淬透性钢、低变形钢、微变形钢、高强度钢、高韧性钢、抗冲击冷变形模具钢。

According to the actual use, the commonly used cold deformation die steels include low hardenability steel, low deformation steel, micro deformation steel, high strength steel, high toughness steel and impact resistant cold deformation die steel.

2、各类冷变形模具钢的特点和相应的处理工艺

2. Characteristics and corresponding treatment processes of various cold deformation die steels

2.1低淬透性冷变形模具钢这类钢以碳素工具钢尤以高碳络钢GCr15和9Cr2Mo等为主：其中以GCr15轴承钢和9Cr2Mo来制作各种成型轧轮和制作冷轧辊为代表，GCr15钢具有良好的耐磨性，但淬透性差，淬火变形大，作为小型冷轧辊(φ≤200m/m)可采用整体加热或整体高温900―950℃快速加热，淬火冷却用盐水→油，控制工件在盐水中的冷却时间而后经200―220℃回火，辊表面硬度控制在Rc60―62之间，能获得较高的使用寿命，如硬度Rc≥62以上易造成辊表面在轧制时产生表面剥落，用GCr15所制的各种成型轧轮可用碱浴等温淬火或用二硝、三硝溶液淬火，控制在溶液中的冷却时间，取出空冷或油冷能使轧轮获得表面高硬度变形小的效果。

2.1 low hardenability cold deformation die steel this kind of steel is mainly carbon tool steel, especially high carbon complex steel GCr15 and 9Cr2Mo. Among them, GCr15 bearing steel and 9Cr2Mo are used to make various forming rollers and cold rollers. GCr15 steel has good wear resistance, but poor hardenability and large quenching deformation. It is used as a small cold roller（ φ ≤ 200m / M) the whole heating or the whole high temperature 900-950 ℃ rapid heating can be adopted, and the quenching cooling uses brine → oil to control the cooling time of the workpiece in the brine, and then after tempering at 200-220 ℃, the surface hardness of the roll is controlled between rc60-62, which can obtain a higher service life. If the hardness RC ≥ 62, it is easy to cause the surface peeling of the roll surface during rolling, All kinds of formed rolling wheels made with GCr15 can be quenched by alkali bath isothermal quenching or by dinitrate and trinitrate solution to control the cooling time in the solution. Taking out air cooling or oil cooling can make the rolling wheels obtain the effect of high surface hardness and small deformation.

随着加工工业的发展，材料改制工业大量的发展，相应的各种高速多辊轧用钢9Cr2Mo何德国轧辊钢86CrMoV7有必要在工业方法上

With the development of processing industry and material restructuring industry, it is necessary to apply various high-speed multi roll rolling steel 9Cr2Mo and German roll steel 86CrMoV7 in industrial methods

要有新的突破，要在强韧化处理上作文章，在采用新的轧辊用钢也要有新的突破。目前在高速轧机的工作辊何传动辊有采用D2(Cr12MOv；Cr12Movco)和5H12(5Cr5MovSi)等。要根据接触挤压疲劳应力和摩擦磨损的观点去选用工作辊的材料，同抗断带来事故的能力去选用传动辊的材料。

New breakthroughs should be made in strengthening and toughening treatment and in the use of new roll steel. At present, D2 (Cr12MoV; cr12movco) and 5H12 (5cr5movsi) are used as work roll and drive roll of high-speed rolling mill. According to the viewpoint of contact extrusion fatigue stress and friction and wear, the material of work roll should be selected, and the material of drive roll should be selected with the ability of anti fracture to cause accidents.