英语 
What is 17-4PH Stainless Steels?
What is 17-4PH Stainless Steels?
1. Introduction of 17-4PH precipitation hardened stainless steels
17-4PH stainless is a kind of precipitation hardened martensitic stainless under American standard. It has lower carbon component, while it has higher Ni & Cr chemicals. And moreover Cu & Nb alloy chemicals have been added into 17-4PH, all these alloy components will help to harden 17-4PH material while it is done heat treatment.
17-4PH, 17 is for Cr % component, 4 for Ni % component, PH is for precipitation hardened.
2. application of 17-4PH precipitation hardened stainless steels
Because of well welding proformance, good anti-corrission property and higher strength and hardness, 17-4PH is always used in industries such as aviation, aerospace, chemical, nuclear, offshore platforms, helicopter, decks, food industry, pulp and paper industry, mechanical parts etc.
3. chemical properties with equivalent material of 17-4PH precipitation hardened stainless steels
STANDARD | GRADE | C | Mn | Si | P | S | Cr | Ni | Cu | Nb |
SAE/AISI | 17-4PH | ≤0.07 | ≤1.0 | ≤1.0 | ≤0.035 | ≤0.03 | 15.5-17.5 | 3.0-6.0 | 3.0-5.0 | 0.15-0.45 |
ASTM A564/A564M | S17400 630 | ≤0.07 | ≤1.0 | ≤1.0 | ≤0.04 | ≤0.03 | 15.0-17.5 | 3.0-5.0 | 3.0-5.0 | 0.15-0.45 |
JIS G4304 | SUS630 | ≤0.07 | ≤1.0 | ≤1.0 | ≤0.04 | ≤0.03 | 15.0-17.5 | 3.0-5.0 | 3.0-5.0 | 0.15-0.45 |
GB/T 20878 | 0Cr17Ni4Cu4Nb (S51740) (05Cr17Ni4Cu4Nb) | ≤0.07 | ≤1.0 | ≤1.0 | ≤0.04 | ≤0.03 | 15.0-17.0 | 3.0-5.0 | 3.0-5.0 | 0.15-0.45 |
EN10088-2 | X5CrNiCuNb16-4 (1.4542) | ≤0.07 | ≤1.5 | ≤0.7 | ≤0.04 | ≤0.015 | 15.0-17.0 | 3.0-5.0 | 3.0-5.0 | 5*C-0.45 |
4. mechanical properties of 17-4PH precipitation hardened stainless steels
Solid | 480℃ aging | 550℃ aging | 580℃ aging | 620℃ aging | |
Tensile Strength (MPa) | - | ≥1310 | ≥1060 | ≥1000 | ≥930 |
Yield Strength (MPa) | - | ≥1180 | ≥1000 | ≥865 | ≥725 |
Elongation (%) | - | ≥10 | ≥12 | ≥13 | ≥116 |
Rate of Area Reduction (%) | - | ≥40 | ≥45 | ≥45 | ≥50 |
Hardness | ≤363HB (≤38HRC) | ≤375HB (≤40HRC) | (≤331HB (≤35HRC) | ≤302HB (≤31HRC) | ≤277HB (≤28HRC) |
Density | 7.80g/cm3 | ||||
5. heat treatment of 17-4PH precipitation hardened stainless steels
Solid | Cooling Temperature (℃) | Cooling Method | |
1 | Yes | 1020~1060 | Quick cooling |
480℃ aging | after | 470~490 | Air cooling |
550℃ aging | after | 540~560 | Air cooling |
580℃ aging | after | 570~590 | Air cooling |
620℃ aging | after | 610~6300 | Air cooling |