Similar Grades:
UNS T41904
Shape: 
Round, Flat, Square.
Size Range:  
Steel-making Condition: 
EF, EF/EAF+LF+VD, EF/EAF+ESR
Delivery Condition:
Annealed , Quenched + Tempered

Surface Condition: 
Black, Grinded, Peeled, Rough turned, Polished

Features:

2.Immediate delivery
3.Premium quality
4.Reliable service
5.MOQ: 1 Ton
  Chemical Composition(%)
 
 
 
Heat treatment
Hardness :Annealed(+A) max: 229 BHN
S4 tool steel when heat-treatment the preheat Temperature need reach 677°C, and the temperature may be ± 14 °C .
S4 tool steel when austenitizing ,should keep 5-15 minutes long. If is the salt bath ,temperature should keep in the 885°C and shall be ± 5.6 °C. Or is the controlled atmosphere furnaces, temperature should keep in the 899°C, and shall be ± 5.6 °C. 
Quenching: S4 tool steel Hardening quenching using oil cooling, and it's hardness min is 58RC. 
Tempering: S4 tool steel general tempering temperature is 204°C. Double tempering of Double tempering of S4 tool steel is recommended.
 
Ultrasonic Test:Material will be ultrasonically tested at appropriate stages of the manufacture to ensure the quality, as agreed between seller and purchaser. 
 
Application:
S4 tool steel are frequently used in cold work applications requiring toughness at relatively high hardness