● Features and application:

 
T8 is a hardened plastic mold steel. After quenching and tempering high hardness and wear resistance, but low thermal rigid, hardenability is poor, deformation, ductility and lower strength. As a need to have a high hardness and wear resistance of tools, such as the shape of a simple mold and punch, metal cutting tools, drilling tools, woodworking cutters, hard drilling, axes, chisels, hand saws vertical , and the fitter assembly tools, dies and other secondary rivet tool.

 
● Chemical Composition:

 
Carbon C: 0.75 ~ 0.84

 
Si Si: ≤ 0.35

 
Manganese Mn: ≤ 0.40

 
Sulfur S: ≤ 0.030

 
Phosphorus P: ≤ 0.035

 
Chromium Cr: allow the residual content of ≤ 0.25, ≤ 0.10 (when manufacturing lead bath quench wire)

 
Ni: to allow the residual content of ≤ 0.20, ≤ 0.12 (when manufacturing lead bath quench wire)

 
Copper Cu: to allow the residual content of ≤ 0.30, ≤ 0.20 (when manufacturing lead bath quench wire)

 
Note: The allows the residual content of Cr + Ni + Cu ≤ 0.40 (when manufacturing lead bath quench wire)

 
● Mechanical Properties:

 
Hardness: Annealed ≤ 187HB, indentation diameter ≥ 4.40mm; quenching ≥ 62HRC

 
● Heat treatment and microstructure specifications:

 
Heat treatment specifications: sample quenching 780 ~ 800 ℃, water-cooled.

 
● Delivery status: the status of delivery of steel to annealing. By mutual agreement, delivery can not annealed state [1]