Nitriding steels

Technical data sheets for nitriding steel grades

Definition and applications

Nitriding steels are a particular category of structural steels used for making machine parts. Once the product has been finished, it undergoes  thermal nitriding,  a process whereby nitrogen is diffused into the surface. This process leads to a hard, wear-resistant surface layer, thanks to the chemical process which enriches the steel with nitrogen. The core keeps the  resistance and toughness of nitrided steel, while very high superficial hardness can be obtained (750/1200HV). Nitriding steels are mostly used in sectors where it is necessary to obtain parts whose  surfaces are hardened for the first 0.05 mm up to 1 mm without having to sacrifice the toughness of the layer, or risk flaking, fracturing, cracking etc. Nitriding steels are highly resistant to corrosion in damp air, fresh water, sea water, and steam at high temperatures.


Nitriding steels have excellent resistance to wear and abrasion, combined with an improved resistance to corrosion in aggressive environments. In fact, the purpose of the nitriding treatment is to create a surface layer which is hardened by a few tenths of a millimeter in order to obtain high resistance to adhesive wear, mechanical abrasion and grip, as well as to  improve the fatigue strength of the piece.


Product range

Steel quality Standard Processing routes Supply status Rounds (mm) Squares (mm) Flats (mm) Blooms (mm)
41CrAlMo7-10 EN 10085 Rolled+Peeled Hardened and tempered stabilized 25-290      
41CrAlMo7-10 EN 10085 Rolled Soft annealed 35-240     200-400
34CrAlNi7-10 EN 10085 Rolled Soft annealed 35-210      

*Blooms: supply status“natural”