Standard: GB / T 3077-1988

Feature
20Cr2Ni4 steel case-hardened steel for high strength alloy with good mechanical properties, its hardenability, strength and toughness are more than 12CrMi3 steel. The good performance of steel forging, forging heating temperature is 1200 ℃, before forging temperature 1150 ℃, final forging temperature is higher than 850 ℃, slow cooling after forging. 20Cr2Ni4 after forging steel such as coarse grains, even after normalizing and subsequent carburizing heating, will be in the thick of the quenched martensite. [1]

Use
Requirements for high strength carburized and quenched structures. Commonly used in the manufacture of small cars, tractor engine and transmission in gear, but also can replace 12CrNi3 steel high performance requirements of the Department of carburizing heart pieces, pieces of cyanide, such as oil drilling and metallurgical pit with teeth and claws cone body.

Chemical composition
Carbon C: 0.17 ~ 0.23

Si Si: 0.17 ~ 0.37

Manganese Mn: 0.30 ~ 0.60

Sulfur S: to allow the residual content of ≤ 0.035

Phosphorus P: allow the residual content ≤ 0.035

Chromium Cr: 1.25 ~ 1.65

Ni-Ni: 3.25 ~ 3.65

Copper Cu: to allow the residual content ≤ 0.030