What is the material of xm- 19 and what is the heat treatment requirement?

XM- 19 stainless steel is a nitrogen strengthened austenitic stainless steel with strong machinability and high weldability. Its yield strength is twice that of 3 16 stainless steel, and its corrosion resistance is equivalent to that of 3 16 stainless steel. XM- 19 stainless steel remains nonmagnetic even after extreme forming. Because of all these advantages, it is usually used in ship shafts, ship hardware, pumps, valves and fasteners.

The machinability of XM- 19 stainless steel is equivalent to that of 3 16 or 3 17 alloy. It is formable, but the elasticity of XM- 19 will be higher than that of other austenitic stainless steels. For maximum hardness, please use cold working. Because XM- 19 has a high tendency of work hardening, the workpiece is annealed after forming to reduce stress.

XM- 19 component

Cr:20.5–23.5

Ni:11.5–13.5

Manganese: 4.0–6.0

Maintenance object:1.5–3.0

Si: lower than Si: 1.0

Fe: allowance

v:0. 1–0.3

Cb:0. 1 -0.3

C: lower than C:0.06

P: lower than P:0.04

S: lower than S:0.03

Mechanical properties of XM- 19

Tensile strength r m: > 380 MPa yield point R p0.2, shrinkage z: > 55% elongation, a: > 35% hardness, HB: > 690 MPa under annealing conditions; 4 15 MPa yield point R p0.2, > 690 MPa shrinkage z: > 50% elongation a: > 30% strain hardening tensile strength r m: >; 725 MPa yield point r p0.2: > 825 MPa shrinkage rate z: > 45% elongation a: > 15%.

application area

The combination of corrosion resistance and mechanical strength is used in ship hardware, pump shaft, petrochemical industry, pulp and paper making, food processing and petroleum industry. Because of its resistance to sulfide stress cracking, it can also be used in "underground" applications.

The field application experience shows that NITRONIC50 stainless steel has excellent sulfide stress cracking resistance under air conditions. In NACE standard Mr 01-75/iso15156-3, the hardness grade of NITRONIC50 under the conditions of annealing and high strength (hot rolling) reaches the maximum value of HRc 35.

Technical specification for heat treatment

1.XM- 19 should be treated by solid solution before processing. Solution treatment can be done by material suppliers or by themselves. The process is as follows: solid solution:1065-1120℃, heat preservation coefficient of 23min/mm, not less than 2 Omin.

2. 17-4PH heat treatment should be solid solution SH aging treatment. The following are two commonly used heat treatment processes: H900 and H 1 1 50. Because of the high hardness after H900 treatment, in order to facilitate processing, the raw materials can be solid-dissolved first, and then aged after semi-finishing and before finishing.

Solid solution S: 1020- 1060℃, thermal insulation coefficient 23min/mm, not less than 2 0min, water cooling. H900:S+470-490℃ for 4h and air cooling. H1150: s1610-630℃, 4h, air cooling.