17-4PH round bar is a widely used martensitic precipitation hardening stainless steel. Its name "17-4PH" comes from its typical chemical composition, which contains about 17% chromium and 4% nickel, while "PH" represents "precipitation hardening". This material is known for its high strength, good corrosion resistance, and excellent processability. HT PIPE is a SS17-4ph supplier with 15+ export experience.
17-4ph stainless steel Product Forms
- Fitting: Flange, Tee, Elbow, Reducer etc.
- Forging: Ring, Shaft, Circle, Block etc.
Delivery status of s17400 round bars
The round rod undergoes solid solution treatment at 1020-1060 ℃ and rapid cooling treatment, with a hardness of <= 28HRC, making it easy for subsequent machining, cold drawing, or forging. It is the most commonly used delivery state.
Timeliness state (H900/H1025/H1150/H1150M): Complete aging strengthening according to customer requirements, deliver finished round bars directly, can eliminate subsequent heat treatment processes, and is suitable for standard parts in mass production.
Only used for round bars that require stress relief during processing, heated to 650-700 ℃ for 2-4 hours, hardness <= 25HRC, suitable for scenarios where stable dimensions are required after complex forming.
Mechanical Properties of 174ph Round Bars
| Yield Strength (Rp0.2) >=MPa | |||||
|---|---|---|---|---|---|
| <=100 | H900 | 1170 | 1310-1450 | 10 | 38-42 HRC |
| 100-200 | H900 | 1100 | 1250-1390 | 9 | 36-40 HRC |
| <=100 | H1025 | 1030 | 1170-1310 | 12 | 35-39 HRC |
| 100-200 | H1025 | 960 | 1100-1240 | 11 | 33-37 HRC |
| <=100 | H1150 | 860 | 965-1100 | 15 | 30-34 HRC |
| 100-200 | H1150 | 800 | 900-1040 | 14 | 28-32 HRC |
| <=100 | H1150M | 790 | 930-1070 | 16 | 28-32 HRC |
| 100-200 | H1150M | 730 | 870-1010 | 15 | 26-30 HRC |
uns s17400 round bar test Size and Shape Inspection
According to ASTM A480 standard, the tolerance for cold drawn round bars (diameter 3-100mm) is grade h9 (± 0.03-0.08mm), and the tolerance for hot-rolled round bars (diameter 10-300mm) is grade h10 (± 0.05-0.15mm).
Cold drawn round bars <= 0.3mm/m, hot-rolled/forged round bars <= 0.5mm/m, detected using a laser straightness detector.
Cold drawn round bars <= 0.01mm, hot-rolled round bars <= 0.03mm, detected using a roundness meter.
stainless steel 17-4ph Surface quality inspection
no cracks, scratches, or oxide scale on the surface, scratch depth <= 0.02mm, detected by visual inspection and roughness tester (Ra <= 0.8 μ m).
There are no cracks, inclusions, or pores on the surface, the thickness of the oxide scale is <= 0.1mm, and there is no residual oxide scale after acid washing.
ss174ph Internal quality inspection
Round bars with a diameter of >= 50mm shall be tested according to ASTM A609 standard B level, and there shall be no internal defects such as delamination or inclusions (defect equivalent <= φ 2mm).
The solid solution round rod has a uniform martensitic structure, and the aged round rod shows uniformly precipitated ε - Cu precipitates without obvious coarse grains.
s17-4ph Mechanics and Corrosion Resistance Testing
Two round bars are randomly inspected for each furnace number, with the sampling location at 1/4 of the diameter of the round bar (to avoid differences in core and surface properties), to test the yield strength, tensile strength, and elongation.
Conduct intergranular corrosion test according to ASTM A262 E method (no cracks), and conduct pitting corrosion test according to ASTM G48 (corrosion rate <= 0.02mm/a).
ss17-4ph bars Typical Applications
Acetic, sulfuric, and phosphoric acid plants, cracked gas quenching systems in ethylene plants and organic synthesis processes containing chlorides.
Seawater cooling piping systems, preheaters, pumps, and piping in seawater desalination plants; and high-pressure seawater systems on ships.
Wet areas most susceptible to corrosion, such as the absorber spray layer, demister, and outlet flue.
Equipment and piping in the pulp bleaching process (ClO₂ environment).
Demanding process steps requiring extreme cleanliness and corrosion resistance.
Wastewater treatment, particularly for industrial wastewater containing high levels of chlorides, sulfides, or acidic components.
