400 Series
Material Range
400 Series
The 400 series group of stainless steels typically have an 11% chromium and 1% manganese increase, above the 300 series group. This stainless steel series tends to be susceptible to rust and corrosion under some conditions although heat-treating will harden them. The 400 series of stainless steels have a higher carbon content, giving it a martensitic crystalline structure that provides the end product with high-strength and high-wear resistance. The 400 series steels tend to be used in agricultural equipment, gas turbine exhaust silencers, hardware, motor shafts, and more.
Characteristics
Ferritic stainless steels are plain chromium stainless steels with a chromium content varying between 10.5 and 18% and a low carbon content. They are magnetic and not hardenable by heat treatment. Ferritic alloys have good ductility and formability but a relatively poor high temperature strength compared to that of austenitic grades.
Martensitic stainless steels were the first stainless steels that were commercially developed (as cutlery) and have a relatively high carbon content (0.1 – 1.2%) compared to other stainless steels. They are plain chromium steels containing between 12 and 18% chromium. They are magnetic and hardenable by quenching and tempering like plain carbon steels and find their main application in cutlery, aerospace and general engineering.
Grades
- 410, 410S, 416, 420, 430, 440C
Chemical composition
| Grades | C | Mn | P | S | N | Si | Cr | Ni | Mo |
|---|---|---|---|---|---|---|---|---|---|
| 410 | 0.15 | 1.0 | 0.04 | 0.03 | - | 1.0 | 11.5/13.5 | - | - |
| 410S | 0.08 | 0.3/0.65 | 0.03 | 0.01 | 0.06 | 0.15/0.5 | 12.0/12.6 | 0.20/0.55 | 0.20/0.55 |
| 416 | 0.15 | 1.25 | 0.06 | 0.15min | - | 1.0 | 12.0-14.0 | - | - |
| 420 | 0.15min | 1.0 | 0.04 | 0.03 | - | 1.0 | 12.0-14.0 | - | - |
| 430 | 0.15 | 1.0 | 0.04 | 0.03 | - | 1.0 | 16.0-18.0 | - | - |
| 440C | 0.95-1.2 | 1.0 | 0.04 | 0.03 | - | 1.0 | 16.0/18.0 | - | 1.75 |