Chemical composition of SK4

Carbon C:0.95 ~ 1.04

Silicon Si: less than or equal to 0.35

Manganese: less than 0.40 Mn

Sulfur: less than 0.030 S

P: less than 0.035 P

Cr Cr: allows residual content less than 0.25, less than 0.10 (manufacturing lead bath quenching steel wire)

Nickel: allows the residual Ni content less than 0.20, less than 0.12 (manufacturinglead bath quenching steel wire)

Cu: allows the residual copper content less than 0.30, less than 0.20 (manufacturinglead bath quenching steel wire)

Note: the allowable residual content of Cr+Ni+Cu is less than or equal to 0.40(manufacturing lead bath quenching steel wire)

Hardness: annealing, is less than or equal to 197HB, the indentation diameter greater than or equal to 4.30mm = 50HRC; quenching, heat treatment and microstructure of SK4 specification

Heat treatment quenching specimen specification: 760 to 780 DEG C, cooling.

Supply hardness:

Soft, semi hard, hard (hard material heat treatment)

The color of the surface:

White, blue, golden color, heat treatment

Delivery state: Steel in annealing state of delivery. By mutual agreement, may also notannealed state of delivery.

SK4化学成分
碳 C ：0.95～1.04
 
硅 Si：≤0.35
 
锰 Mn：≤0.40
 
硫 S ：≤0.030
 
磷 P ：≤0.035
 
铬 Cr：允许残余含量≤0.25、≤0.10(制造铅浴淬火钢丝时)
 
镍 Ni：允许残余含量≤0.20、≤0.12(制造铅浴淬火钢丝时)
 
铜 Cu：允许残余含量≤0.30、≤0.20(制造铅浴淬火钢丝时)
 
注：允许残余含量Cr+Ni+Cu≤0.40(制造铅浴淬火钢丝时)
 
硬度 ：退火,≤197HB,压痕直径≥4.30mm;淬火,≥50HRC                                                                                                       sk4热处理规范及金相组织
热处理规范：试样淬火760～780℃,水冷。
供货硬度：
软态、半硬、硬态（热处理硬料）
表面颜色：
白色、蓝色、金黄、热处理原色
交货状态：钢材以退火状态交货。经双方协议，也可以不退火状态交货。