Professional Stainless Steel Round Bar Supplier
If you require a custom product with diameters Ø3–300 mm and ISO 286 h9, h10, h11 tolerances, SparkX can meet all your needs. Our stainless steel round bar straightness can reach ≤ 0.55mm/m, and SparkX provides cold-drawn, peeled, turned, and centerless ground finishing treatments; you can choose whichever you want. You can also choose annealing, Q&T, and aging suitable for grades 303, 304/304L, 316/316L, 321, 410, 420, 431, 416, 17-4PH, 2205, and more.
Applicable standards include ASTM A276/A276M for general stainless steel bars, ASTM A479/A479M for pressure-vessel applications, ASTM A582/A582M for free-machining grades, ASTM A564/A564M for precipitation-hardening grades, and EN 10088-3.
We are a stainless steel manufacturer with 35 years of experience, and our factory covers over 60000㎡. All stainless steel round bars can be saw-cut to length, chamfered, rust-protected, and hex-bundled. Please send us your drawing and tolerance, and we will return a 24-hour quote with a machining-friendly proposal and a stable lead time.
Our Other Grades of Stainless Steel Round Bars
If you have any other needs or require customization, please feel free to contact us.
Heat-resistant ferritic round bar and very suitable for exhaust systems and automotive parts, with good oxidation resistance and economical corrosion resistance.
Widely used austenitic stainless steel round bar, suitable for machining and manufacturing.
Heat-treatable martensitic stainless steel has higher hardness and wear resistance, suitable for shafts, valves and mechanical parts.
Easy machining martensitic stainless steel with added sulfur, ideal for high speed machining of pipe fittings, fasteners and precision parts.
Molybdenum-bearing austenitic stainless steel with improved resistance to chloride-containing environments. 316L is preferred where lower carbon content is required, including many welded applications.
High-strength martensitic stainless steel with improved corrosion resistance, suitable for marine shafts, pumps and high load parts.
Hardenable martensitic stainless steel with high hardness and edge retention, common for blades, molds and wear parts.
Economical austenitic bar with good strength and formability, ideal for indoor applications and moderately corrosive environments.
Chromium-nickel-manganese austenitic stainless steel used for general fabrication, hardware and decorative components.
Easy machining austenitic bar, suitable for precision machined parts, has excellent machinability and maintains good corrosion resistance.
How We Control Dimensional Accuracy & Straightness of Stainless Steel Round Bar
Accuracy and Straightness are always at the core of our stainless steel round bars. Billets are cold-drawn and straightened, and peeled or turned to remove finishing defects, and centerless ground to the target diameter. Through rigorous measurement and final inspection, we can meet ISO286 h9/h10/h11 tolerances. The key specifications include straightness ≤0.55mm/m, and verification reports are provided. This means our stainless steel round has less spindle runout and easier automatic feeding, with fewer secondary corrections
Surface Integrity & Finish for Stainless Steel Round Bar
Surface quality is also important for stainless steel round bars. Peeling/turning eliminates seams, laps, and decarburized finishes, and centerless grinding delivers a uniform finish with a defined Ra window. It’s very suitable for machining or plating, or polishing. If you require, we can pickle or passivate it and apply anti-rust oil. We wrap the stainless steel round bars with PE film and end caps for impact-resistant transportation. You will receive a consistent appearance and a clean surface, and no need to rework stainless steel round bars. You can use them right away.
Heat Treatment & Property Control of Stainless Steel Round Bars
We match mechanical properties to your application. Generally, austenitic grades 304,316 are solution annealed and rapidly quenched to ensure corrosion resistance and ductility. Martensitic grades 410, 420, 431 receive quench and temper to balance hardness and toughness. Precipitation hardening 17-4PH is aged to H900-H1150 as specified, duplex 2205 is solution annealed and water quenched to avoid embrittlement. Stress relief can be added for tight tolerance machining, and the resulting hardness, UTS, and elongation ranges are all recorded on the EN 10204 3.1 MTC. You get stainless steel round bars that cut predictably and hold size after machining, and meet the strength and corrosion balance your part demands.
It depends on grade and alloy(Ni/Mo content), process route(hot rolled/peeled/turned/centerless ground), heat treatment(solution, quench and temper, aging), size and length, tolerance class & straightness (ISO 286 h9/h10/h11; ≤0.5 mm/m on request), quantity/MOQ, cutting, export packing & Incoterm, and market surcharges. Please send your grade, size, length, finish, tolerance class & straightness (ISO 286 h9/h10/h11; ≤0.5 mm/m on request), quantity/MOQ, cutting, export packing & Incoterm.
We supply Ø3-300 mm with standard 3 m / 6 m lengths, and cutting to lengths of 0.5–6m is available. If you will be turning or grinding later, we recommend you choose a slightly larger size to reserve machining allowance. We recommend h11 for roughing, h10 for general shafts, and h9 for precision. Standard straightness is ≤1.0 mm/m, and ≤0.55 mm/m can be agreed for critical shafts. Share your drawing, and our team will map the grade, tolerance, and straightness to your application.
Shafts, pins, couplings: 304/304L or 316/316L; for higher strength, select 431 or 17-4PH (ground h9/h10 recommended).
Fasteners (bolts, studs, nuts): 304/316 for corrosion resistance; 410/420 when hardenability is needed; 2205 for chloride-rich sites.
CNC-machined blocks/manifolds: 303 for free-machining; choose 304/316 when welding or higher corrosion resistance is required.
Marine hardware: 316/316L; upgrade to 2205 under heavy chlorides/splash zones.
Food & medical equipment: 304/316L, passivated, clean surface.
Chemical / pulp & paper: 316L / 2205.
Higher temperature parts: 321 / 309 / 310 (on request).
