Surface Hardening Steels

Steels for surface hardening by induction

The series of carbon steels for surface tempering includes four types of materials with an increasing carbon content. The hardness that can be obtained on a surface hardened with this treatment is directly proportional to the steel’s carbon content.

All of these steels have a balanced chemical composition that allows a good machinability (S = 0.020 – 0.040) and an excellent repeatability of the heat treatment thanks to the constant size of the austenitic grain (Al = 0.020 – 0.050).

The required hardness values can only be obtained with certainty after the removal of the bar’s surface layer to eliminate any decarburization.

The heat treatments available for this type of steel – to be checked on a case-by-case basis according to the different qualities – are: rolled natural, workable annealed, isothermal annealed, globular annealed, normalized, and quenched and tempered.

	Execution	Profile	Range (mm)	Finish	Tolerances
Bars	Rolled	Round	20÷200	Raw, peeled iron product	-
	Drawn	Round Hexagonal Square	3÷70 3÷70 4÷60	Polished	ISA h9-h10-h11
	Peeled - rolled	Round	20÷100	Polished	ISA h9-h10-h11
	Ground	Round	50÷60	Polished	ISA h7-h8-h9-h10-h11
Coils	Drawn	Round Hexagonal Square	2÷22 3÷12 4÷12	Polished, phosphated	ISA h9-h10-h11