Specialty Stainless Steel Processes


Specialty stainless steel processes (S3P) featuring Kolsterising® and Nivox® technology offer unique surface hardening solutions for austenitic stainless steel, nickel-based alloys and cobalt-chromium alloys producing increased mechanical and wear properties without adversely affecting corrosion resistance.
Austenitic stainless steel parts improve their mechanical properties by applying the S3P processes, resulting in hardened austenitic stainless steel surfaces. In all S3P processes, the corrosion of the base material is not altered, while exhibiting superior wear resistance, strength and ductility, as well as resistance to galling.
As surface diffusion processes, the surfaces do not crack or chip, offering significant advantages over coating technologies. S3P A® and Kolsterising® are the state of the art processes for austenitic stainless steel, duplex stainless and nickel-based materials. S3P M is used for the treatment of martensitic and precipitation hardened stainless steel materials.

Benefits include:

– Increased surface hardness to 900-1300 HV0.05 (depending on base material and surface conditions)
– Properly selected and designed materials and parts maintain corrosion resistance
– Treated parts offer colour and dimensional stability
– No post treatment is necessary
– No risk of delamination
– The paramagnetic properties of austenitic materials remain unchanged after treatment
– Eliminates fretting and galling
– Highly resistant to surface wear environments such as sliding in combination with abrasive wear and cavitation erosion..

Applications and materials:

– Non-galling wear resistant demands of industrial fluid handling pumps, valves and fittings
– Fasteners that need to maintain their corrosion resistance, to be non galling and wear resistant, and may need to be disassembled easily
– Wear and scratch resistant parts and fasteners that maintain corrosion resistance used in marine applications

All stainless steel as well as nickel-based alloys we use can be treated by various S3P processes.
Some typical examples are:

– Austenitic stainless steel: AISI 304, 304L, 316, 316L
– Duplex stainless steel: AISI 430, 440
– Precipitation hardened stainless steel: PH 17-4, PH 13-8 Mo
– Nickel Based Alloys: Hastelloy® e Inconel®

S3P treatments involve low temperature diffusion of large quantities of carbon and/or nitrogen into the surface without the formation of chromium precipitations. No additional chemical elements that were not already present prior to the treatment are introduced during the process. There is no risk of delamination because S3P processes neither add a coating nor introduce brittle phases in the material.