To achieve a good quality kolsterised product in terms of corrosion
resistance and wear resistance, it is very important to keep the contents of
Delta Ferrite and Distortion Martensite to a minimum.
We recommend to
specify a zero-content Delta Ferrite when purchasing your material.
The
Martensite which is produced during machining can be eliminated by a solution
annealing process.
Ferritic (< 0,1%C, 13-18%Cr, no Ni)eg. W.-Nr. 1.4016
(AISI 430F / X8 Cr17)
Martensitic (0,2 - 1,10%C,
12-18%Cr, 0-2,5%Ni) eg. W.-Nr. 1.4112 (AISI 440 B / X90
CrMoV18)
Austenitic (< 0,1%C, 16-26%Cr, 4-22%Ni) eg.
W.-Nr. 1.4401 (AISI 316 / X2 CrNiMo 17 12)
Duplex (
<0,1%C, 21-28%Cr, 3-7%Ni, N) eg. W.-Nr. 1.4462 (SAF 2205 / X2 CrNiMoN 22 5
3)
Without Molybdenum (304)
With Molybdenum (316)
L-Grades
(316L)
Stabilised (321)
Free machining (303)
In principle, any austenitic stainless steel can be kolsterised. However, the preferred type is one containing molybdenum. In addition to that Duplex stainless steel and some Nickel base alloys can be kolsterised. The table contains a selection of treatable materials and characteristics of the base material.
These are the most common materials to be kolsterised. If you have any other
material, we will be pleased to check whether it is treatable.
Examples
of treatable materials: