Mar 5 2013
Topics Covered
Introduction
Chemical Composition
Mechanical Properties
Other Designations
Manufacturing Process
Introduction
Stainless steel grade 442 is a ferritic type steel that is one of the most widely used precipitation hardening grades in various industries. Although soft and ductile in the solution annealed condition, it is capable of high properties with a single precipitation or aging treatment. This material also has good corrosion resistance, high harness, toughness and strength.
The following datasheet provides an overview of stainless steel grade 442.
Chemical Composition
The chemical composition of grade 442 stainless steel is outlined in the following table.
|
Element |
Content (%) |
|
Chromium, Cr |
18-23 |
|
Silicon, Si |
1 |
|
Manganese, Mn |
1 |
|
Phosphorous, P |
0.04 |
|
Carbon, C |
0.20 |
|
Sulfur, S |
0.03 |
Mechanical Properties
The mechanical properties of grade 442 stainless steel are displayed in the following table.
|
Properties |
Metric |
Imperial |
|
Tensile strength |
515-550 MPa |
74700-79800 psi |
|
Yield strength (@strain 0.200 %) |
275-310 MPa |
39900-45000 psi |
|
Modulus of elasticity |
200-215 GPa |
29000- 31200 ksi |
|
Shear modulus |
80-83.GPa |
11600- 12000 ksi |
|
Poisson’s ratio |
0.270-0.290 |
0.270-0.290 |
|
Elongation at break (In 2", 50% cold worked) |
2.80% |
2.80% |
|
Hardness, Rockwell B (annealed) |
90- 95 |
90-95 |
Other Designations
Equivalent materials to grade 442 stainless steel are given below:
-
ASTM A176
-
SAE 51442
-
SAE J405 (51442)
Manufacturing Process
Machining of grade 442 stainless steel produces long, gummy chips. It is possible to machine the material in annealed condition. Post-machining solution treatment of parts is recommended prior to final hardening if machining in this condition. Heat treatment can be performed by soaking the steel at 1038°C (1900°F) for 30 min and cooling below 16°C (60°F) for full martensite transformation. Common fusion and resistance methods can be used to weld grade 442 steel. Oxyacetylene welding should not be used. If necessary, AWS E/ER630 filler metal can be used. Forging can be performed by soaking the material at 1177°C (2150°F) before forging. It should not be forged below 1010°C (1850°F). Post-work solution treatment is required before final hardening.