17-4 stainless is an age-hardening martensitic stainless combining high strength with the corrosion resistance of stainless steel. Hardening is achieved by a short-time, simple low-temperature treatment. Unlike conventional martensitic stainless steels, such as type 410, 17-4 is quite weldable. The strength, corrosion resistance and simplified fabrication can make 17-4 stainless a cost-effective replacement for high strength carbon steels as well as other stainless grades.
At the solution treating temperature, 1900°F, the metal is austenitic but undergoes transformation to a low-carbon martensitic structure during cooling to room temperature. This transformation is not complete until the temperature drops to 90°F. Subsequent heating to temperatures of 900-1150°F for one to four hours precipitation strengthens the alloy. This hardening treatment also tempers the martensitic structure, increasing ductility and toughness.
17-4PH Chemical Composition
C |
Cr |
Ni |
Si |
Mn |
P |
S |
Cu |
Nb+Ta |
≤0.07 |
15.0-17.5 |
3.0-5.0 |
≤1.0 |
≤1.0 |
≤0.035 |
≤0.03 |
3.0-5.0 |
0.15-0.45 |
17-4PH Physical Properties
Density |
Specific heat capacity |
Melting point |
Thermal conductivity |
Elastic modulus |
7.78 |
502 |
1400-1440 |
17.0 |
191 |
17-4PH Mechanical Properties
Condition |
бb/N/mm2 |
б0.2/N/mm2 |
δ5/% |
ψ |
HRC |
|
Precipitation |
480℃ageing |
1310 |
1180 |
10 |
35 |
≥40 |
550℃ageing |
1070 |
1000 |
12 |
45 |
≥35 |
|
580℃ageing |
1000 |
865 |
13 |
45 |
≥31 |
|
620℃ageing |
930 |
725 |
16 |
50 |
≥28 |
AMS 5604, AMS 5643, AMS 5825,ASME SA 564, ASME SA 693, ASME SA 705, ASME Type 630,ASTM A 564, ASTM A 693, ASTM A 705, ASTM Type 630
Condition A – H1150,ISO 15156-3,NACE MR0175,S17400,UNS S17400,W. Nr./EN 1.4548
Round bars/Flat bars/Hex bars, Size From 8.0mm-320mm, Used for bolts,fastners and other spare parts
Supply in welding wire and spring wire in coil form and cut length.
Spring with according to clients drawing or specification
Widths up to 1500mm and lengths up to 6000mm,Thickness from 0.1mm to 100mm.
Standards size and customized dimension can be produced by us with small tolerance
Soft condition and hard condition with AB bright surface, width up to 1000mm
17-4PH in forms of Bolts,screws,flanges and other fasterners, according to clients specification.
• Easy to adjust the strength level, that is through the changes in heat treatment process to adjust martensite phase transformation and aging
treatment of metal forming precipitation hardening phase.
• Corrosion fatigue resistance and water resistance.
• Welding:In the condition of solid solution,ageing or overageing ,the alloy can be welded in ang way, without preheating.
If demanding the welding strength close to the steel strength of ageing hardened, then the alloy must be solid solution and ageing treatment after welding.
This alloy is also suitable for brazing, and the best brazing temperature is the solution temperature.
• Corrosion resistance:Alloy corrosion resistance is superior to any other standard hardenable stainless steel, in the static water easy suffer from erosion corrosion or cracks.In the petroleum chemical industry, food processing and paper industry with good corrosion resistance.
• Offshore platforms, the helicopter deck, other platforms.
• Food industry.
• Pulp and paper industry.
• Space (turbine blade).
• Mechanical parts.
• Nuclear waste barrels.