But it should be tempered for any heavy use.
4140 steel heat treatment hardness.
1 4140 is an ok die steel but is not recommended for radical shaped dies such as narrow fullering crown and so on.
4140 has a nominal carbon content of 4 and this carbon content will yield a hardness of rc 51 for a 90 martensitic structure 9th edition of the asm material handbook volume i.
This leaves near full hardness.
3 tempering recommendations from the asm heat treaters guide for 4140 4142 is a minimum of 400 f.
2 fully hardened 4140 ranges from 54 to 59 hrc.
4140hw alloy steel technical data 4140hw meets aisi4140 standards and has improved hardenability and strength in heavier cross sections.
Aisi 4140 alloy steel can be tempered at 205 to 649 c 400 to 1200 f depending upon the desired hardness level.
The section size in which maximum hardness can be obtained depends on alloy content.
Aisi 4140 alloy steel can be hardened by cold working or heating and quenching.
For example a tensile strength of 225 ksi can be achieved by tempering at 316 c 600 f and tensile strength of 130 ksi can be achieved by tempering at 538 c 1000 f.
Tempering reheating after quenching will achieve the desired hardness range.
Heat treatment to 845 c slow cooling from 755 c at a rate of 14 c 25 f hour to 665 c or rapid cooling to 675 c for 5 hours isothermal annealing.
You find 4140hw in a.
Alloy description timkensteel s 4140hw grade is a fine grained low alloy steel that offers optimum heat treat response in heavier cross sections.