431 stainless steel round bar black finish heat treatment hardness qualified UT test
Description:
Cr steel with Ni in 431(16cr-2ni) has high mechanical properties through heat treatment, and is superior to 410 and 430 steel in corrosion resistance.The 431 stainless steel corresponds to Chinese 1Cr17Ni2 and Japanese JIS SUS431, Germany X22CrNi17.
Diameter tolerance: +1.5~+3.0mm
Chemical Composition:
| Compsition | C Max% | Si Max% | Mn Max% | P Max% | S Max% | Cr% | NI% |
| 410 | 0.15 | 1.0 | 1.0 | 0.04 | 0.03 | 11.5-13.5 | -- |
| 420 | 0.025 | 1.0 | 1.0 | 0.04 | 0.03 | 12.0-14.0 | -- |
| 430 | 0.12 | 0.75 | 1.0 | 0.04 | 0.03 | 16.0-19.0 | -- |
| 431 | 0.20 | 1.0 | 1.0 | 0.04 | 0.03 | 15.0-17.0 | 1.25-2.5 |
Mechanical properties:
Tensile strength σb (MPa): quenching and tempering, ≥1080
Elongation δ5 (%): quenching and tempering, ≥10
Impact work Akv (J): quenching and tempering, ≥39
Hardness: annealing, ≤ 285HB
Heat treatment specification and metallographic structure: heat treatment specifications:
1) annealing, tempering at 680-700 °C for high temperature tempering;
2) quenching, oil cooling at 950 to 1050 °C;
3) tempering at 275 to 350 °C.
Metallographic organization: The tissue is characterized by martensite type.
Delivery status: generally delivered in heat treatment state, the type of heat treatment is indicated in the contract; if not specified, it is delivered according to the state without heat treatment.
Tolerance of bright polished bar:
| Tolerance | h7 | h8 | h9 | h10 | h11 | f7 | f8 |
| OD mm | |||||||
| 6-10 | 0-0.015 | 0-0.022 | 0-0.036 | 0-0.058 | 0-0.09 | -0.013 -0.028 |
-0.013 -0.035 |
| 10-18 | 0-0.018 | 0-0.027 | 0-0.043 | 0-0.058 | 0-0.09 | -0.016 -0.034 |
-0.016 -0.043 |
| 18-30 | 0-0.021 | 0-0.033 | 0-0.052 | 0-0.084 | 0-0.13 | -0.02 -0.041 |
-0.02 -0.053 |
| 30-50 | 0-0.025 | 0-0.039 | 0-0.062 | 0-0.1 | 0-0.16 | -0.025 -0.05 |
-0.025 -0.064 |
| 50-80 | 0-0.030 | 0-0.046 | 0-0.074 | 0-0.12 | 0-0.19 | -0.03 -0.06 |
-0.03 -0.076 |
| 80-120 | 0-0.035 | 0-0.054 | 0-0.087 | 0-0.14 | 0-0.22 | -0.036 -0.071 |
-0.036 -0.9 |
