Product List
Gangsteel Material Solution
Email: admin@gangsteel.com
Sales: jack@gangsteel.com
Published: November 7, 2025 | Updated: November 7, 2025By Gangsteel Engineering Team – 25+ Years in Stainless Steel Export Excellence
In the high-stakes arena of industrial bar stock, where every MPa of yield and every percentage of elongation can make or break a component's lifespan, ASTM A479 UNS S41500 emerges as a powerhouse. This martensitic stainless steel bar specification has been the backbone of countless projects at Gangsteel, our China-based production and export hub that's shipped over 20,000 tons of similar alloys to clients in petrochemical, offshore, and power sectors worldwide. If you're an engineer calculating torque loads for a compressor rod or a buyer scouting equivalents to cut costs without compromising compliance, this guide delivers the straight talk on specs, equivalents, and why S41500 bars are worth their weight in reliability.
Think back to a 2023 overhaul at a Canadian tar sands facility: our A479 UNS S41500 bars, machined into 300mm diameter pump shafts, shrugged off abrasive slurries and -40°C winters for 18 months straight—no pitting, no fractures. That's the essence of this grade: a low-carbon martensitic alloy (F6NM family) with chromium for corrosion barriers, nickel for austenite stability, and molybdenum for that extra edge against chlorides. In this detailed rundown, we'll cover bar specs from chemistry to mechanics, cross-reference equivalents, and share procurement pointers. Grounded in our mill's daily outputs and third-party audits, this isn't textbook theory—it's forged-in-fire knowledge to empower your next spec.
ASTM A479 outlines stainless steel bars and shapes for boiler, pressure vessel, and general service, with UNS S41500 tailored for martensitic needs where strength trumps ductility. Bars under this spec—rounds, squares, flats—undergo hot-finishing or cold-drawing for precision, making them ideal for machined parts like valve stems or turbine spindles. S41500's PREN around 19 positions it between basic 410 (PREN 11) and duplex 2205 (PREN 35): tough enough for moderate corrosives, machinable enough for high-volume runs.
At Gangsteel, we produce these bars from AOD-refined melts, ensuring low gas content for superior ultrasonic cleanliness (ASTM A388 Level 2). Density at 7.85 g/cm³ keeps them lightweight for long lengths (up to 12m standard), while the spec's heat-treat flexibility unlocks yield strengths over 620 MPa without brittleness. We've seen S41500 bars extend MTBF (Mean Time Between Failures) by 40% in sour gas pumps compared to carbon steels—real savings in downtime. For flat counterparts, consider integrating with UNS stainless steel plates for welded assemblies.
A479 demands rigorous melt controls and testing for UNS S41500 bars, from spectrometry for elements to tensile pulls on machined samples. Gangsteel enhances this with in-line eddy current for surface defects, shipping only bars that ace 100% inspection.
The alloy's makeup prioritizes low impurities for weldability and phase stability, with Cr/Ni/Mo synergizing for martensitic hardening without delta ferrite excess.
|
Element |
% Range (ASTM A479) |
Gangsteel Typical Melt |
Impact on Bar Properties |
|---|---|---|---|
|
Carbon (C) |
0.05 max |
0.02-0.04 |
Minimizes carbide formation; ensures bars remain ductile post-temper. |
|
Manganese (Mn) |
0.50-1.00 |
0.60-0.80 |
Aids hardenability; refines grain for uniform bar cross-sections. |
|
Silicon (Si) |
0.60 max |
0.30-0.50 |
Deoxidizes melt; controls flow in hot-rolling for straight bars. |
|
Phosphorus (P) |
0.030 max |
<0.015 |
Low to prevent segregation; boosts transverse strength in drawn bars. |
|
Sulfur (S) |
0.030 max |
<0.010 |
Trace for chip-breaking in machining; balanced to avoid hot cracks. |
|
Chromium (Cr) |
11.50-14.00 |
12.50-13.20 |
Builds passive films; elevates yield by solid solution strengthening. |
|
Molybdenum (Mo) |
0.50-1.00 |
0.60-0.80 |
Fights localized corrosion; enhances creep resistance in hot bars. |
|
Nickel (Ni) |
3.50-5.50 |
4.20-4.80 |
Stabilizes austenite; improves low-temp toughness without softening. |
|
Nitrogen (N) |
0.10 max |
<0.05 |
Interstitial booster; limited to prevent gas pores in bars. |
|
Iron (Fe) |
Balance |
>82.00 |
Core matrix—our VIM process yields high purity for fatigue endurance. |
These values lock in A479 compliance, with Gangsteel's low-P/S options for premium sour service. Every bar shipment includes EN 10204 3.1 certs, traceable to the heat.
After annealing (1010-1120°C) and tempering (565-760°C), A479 UNS S41500 bars achieve martensitic excellence. Longitudinal tests per ASTM E8 reveal:
|
Property |
Min Value (Annealed + Tempered) |
Typical Gangsteel Bar |
Bar Application Notes |
|---|---|---|---|
|
Tensile Strength (MPa) |
795 |
850-920 |
Foundations for high-torque rods; we've tensioned 950 MPa in 200mm bars. |
|
Yield Strength (0.2% Offset, MPa) |
620 |
680-750 |
Critical for elastic recovery in springs; exceeds for safety in stems. |
|
Elongation (%) |
15 (in 50mm) |
18-22 |
Ensures bendability; vital for cold-drawn hex bars. |
|
Hardness (HRB) |
32 max |
25-30 |
Soft for turning; tempers to HRB 28 for wear in bushings. |
|
Reduction of Area (%) |
40 |
45-55 |
Measures necking; key for upset forging ends. |
|
Charpy V-Notch Impact (J) |
27 @ -18°C |
32-40 @ -46°C |
Absorbs vibrations; NACE-tuned for no ductile-brittle shift. |
At 300°C, tensile holds 90%; cryogenic (-196°C) boosts yield 15%. Our accredited labs confirm these via full-size bar pulls, showing S41500 outperforming 410 by 30% in impacts.
Bars ship annealed, but max strength comes from: austenitize 1050°C, quench air/oil, temper 620°C/2hrs. This tempers martensite for HRB 28-32, avoiding sigma phase (425-540°C taboo). Machining: SFM 80-120 with carbide, coolant to prevent galling. Common snag: Under-tempering leads to >32 HRB— we've re-treated batches to restore compliance.
For spec synergy, A479 bars pair with ASTM A240 /A240M sheets in fabrications.
A479 UNS S41500 bars translate seamlessly abroad, easing multi-standard sourcing. Gangsteel dual-certs for efficiency.
Vs. equivalents like 17-4PH, S41500 yields 620 MPa at lower cost, trading some corrosion for machinability gains. In a 2024 German auto swap, we equated S41500 to 1.4313 bars, trimming lead times 20%. For ASME needs, explore ASME SA240/SA240M variants.
These bars anchor sour wellheads (API 6A), spin mixer shafts in chemicals, and brace landing gear in aviation. In renewables, they're axles for wind turbines, resisting fatigue.
Gangsteel example: 2025, a UAE desalination plant used 10 tons of 100mm S41500 bars for pump rods—handled 150°C brine without scaling, per ABS inspections. Or a U.S. fracker's 80mm squares in valves: 30% longer life vs. 316, saving $150K in swaps.
November 2025 rates for A479 S41500 bars: $2,600-2,800 USD per ton FOB, flat despite Ni ups. Rounds: $2,600; peeled +$200/ton.
Gangsteel advantages: In-house drawing, 99% acceptance. Tie in UNS S41500 stainless steel plate for kits.
Q: What are the key specs for ASTM A479 UNS S41500 bars?
A: Chem: C 0.05 max, Cr 11.5-14.0%, Ni 3.5-5.5%; Mech: Tensile 795 MPa min, yield 620 MPa min, elongation 15% min, HRB 32 max. Bars for pressure/general use; Gangsteel's hit 900 MPa tensile in 150mm rounds for enhanced torque.
Q: How do A479 UNS S41500 bars stack against 17-4PH?
A: Similar yield (620 vs. 760 MPa), but S41500 machines 20% easier at lower cost—PREN 19 for moderate corrosives. Equivalents excel in sour vs. duplex's chlorides. Swapped in a 2024 aero bar run, saving 25% on tooling.
Q: What's the price range for A479 UNS S41500 bars today?
A: $2,600-2,800/ton FOB; bulk to $2,500. Q4 steady; factors like diameter add $100-200/ton. Our exports undercut EU by 30% via scale—quotes include spec breakdowns.
Q: Are A479 UNS S41500 bars suited for NACE sour service?
A: Yes—MR0175 compliant at HRB <32, HIC-resistant. Yield 620 MPa handles 15% H2S/120°C. Delivered 12 tons to BP; passed 750-hr tests without SSC.
Q: Optimal heat treatment for A479 S41500 bars?
A: Austenitize 1050°C, quench air, temper 620°C/2hrs for HRB 28-32. Elongation reaches 20%; skip 425-540°C to avoid embrittlement. Our protocols yield full uniformity in 400mm bars.
Q: Top equivalents for ASTM A479 UNS S41500 bars?
A: ASME SA479 (pressure), EN 1.4313 (EU bars). SA479 for vessels; 1.4313 for DIN. Dual-certified at Gangsteel—accelerated a Swiss client's approval by 35 days.
Q: How is quality assured for A479 UNS S41500 bars?
A: 100% UT (A479 S12), tensile E8, chem A751. ISO 9001 facilities; 2025 zero returns. Complements ASTM A240 /A240M for bar-sheet pairs.
Q: Lead times and MOQ for custom A479 UNS S41500 bars?
A: MOQ 500 kg; stock 10 days, custom 25. Expedite +$150/ton for 7 days. Air-freighted 4 tons to Australia in 9 days amid shortages.
ASTM A516 GR 70 equivalent materials is such as ASME SA516 GR 70, EN 10028 P355GH, and BS1501 224-490 A & B, sh
we supply high-quality A516 Gr 70 steel plate for pressure vessel applications and other standards like ASTM A2
EN10028-2 P355GH for High-Strength Low-Alloy Columbium-Vanadium Structural Steel EN10025-2 S355J2 Structural St
We export A240 304L Stainless Coil 2B, NO.1 No.4 surface, the thickness 0.1mm to 3mm, 3mm to 22mm, Mother mill
