5CrNiMo 
 Alloy tool steel: 5CrNiMo Standard: GB / T 1299-1985 ● Features and Scope: 5CrNiMo steel has good toughness, strength and high wear resistance. It at room temperature and 500 ~ 600 ℃ when the mechanical properties of almost the same. Heated to 500 ℃, can still hold about the hardness of HB300. As the steel contains molybdenum, which is not sensitive to the temper brittleness. Slowly cooled down from 600 ℃ after the impact toughness is only slightly reduced. 5CrNiMo steel has good hardenability. 300mm × 400mm × 300mm chunks of steel materials, oil quenched from 820 ℃ and 560 ℃ tempered, cross-section of various parts of the hardness is almost the same. The various kinds of steel used to make large and medium-sized forging die. This kind of steel is easy to form the white point, the need for strict control of smelting and forging process of cooling after rolling system of foreign steel 5CrNiMo similar ingredients: United States L6 (AISI), Japan SKT4 (JIS) Japanese GFA (Datong) Japan DM (Hitachi), Germany 1.2713 (W-Nr) France 55NiCrMoV7 (NF). Main technical parameters: quenching: 58 
 Quenching temperature ℃: 830 ~ 860 
 Delivery condition: Annealed HB ≤ 241 
 Coolant: Oil Oil 
 Chemical Composition: C: 0.50 ~ 0.60 Si Si: ≤ 0.40 Manganese Mn: 0.50 ~ 0.80 S S: ≤ 0.030 P P: ≤ 0.030 Cr-Cr: 0.50 ~ 0.80 Ni-Ni: 1.40 ~ 1.80 Copper Cu: ≤ 0.30 to allow the residual content Vanadium V: allow the residual content of <0.2 Mo Mo: 0.15 ~ 0.30 Mechanical Properties: Hardness: Annealed, 241 ~ 197HB, indentation diameter of 3.9 ~ 4.3mm standard heat treatment and microstructure: heat treatment specifications: quenching, 830 ~ 860 ℃ oil cooling . Delivery status: Delivery of steel in the annealed condition. 5CrNiMo main purpose for making a variety of materials of complex shape, a large impact load, operating temperature is not too high, side length> 400mm medium-sized forging die and trimming die. For the manufacture of the general shape of a simple manufacturing process smelting steel vacuum refining process to ensure pure; heat treatment used to make large-scale professional pre-hardened steel for best results, hardness evenly distributed. 
 CrNiMo tempering process 
 The recommended specifications of steel quenching 5CrNiMo quenching temperature / ℃ cooling Hardness (HRC) 
 Medium temperature / ℃ extension 
 830 ~ 860 oil 20 30 至 150 ~ 180 ℃ 53 ~ 58 immediately after tempering 
 Note: 1. Large-scale mold quenching temperature using the upper limit of the small mold (the length was 200 ~ 300mm or less) using the lower limit; 2 die forging hammer in order to avoid quenching produces a large stress and strain, from 830 ~ 860 ℃ After heating, the first pre-cooling in air to 750 ~ 780 ℃, and then oil-cooling to about 150 ~ 180 ℃, remove and immediately tempered; 3 for large molds should be placed on the furnace 600 ~ 650 ℃ in the pre- heat, heat through and then the furnace temperature increases; for heating better to die on the 60 ~ 100mm high heat on the plate.