Stainless steel bar is produced in round, square, flat, and hexagon shapes conforming to ASTM standards and specifications, typically ASTM A276 and ASTM A476, stainless steel materials include standard 304, 304L, 316, 316L, 321 and 400 series grades. Stainless steel bars are widely used in automotive parts, aerospace, hardware tools, chemical industry and other fields due to its good corrosion resistance, heat resistance, low temperature strength and mechanical properties.
Stainless steel bars can be divided into hot-rolled, forged and cold-drawn according to the production process. The specification of hot rolled stainless steel round steel is 5.5-250mm. Among them: 5.5-25 mm of small stainless steel round steel is mostly supplied in bundles of straight bars, commonly used for rebar, bolts and various mechanical parts; greater than 25 mm of stainless steel round steel, mainly used for the manufacture of mechanical parts or for seamless steel pipe billets.
Stainless Steel Bar Specifications
- ASTM A276 / A276M-Standard Specification for Stainless Steel Bars and Shapes
- ASTM A479 / A479M-Standard Specification for Stainless Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels
- ASTM A484 / A484M-Standard Specification for General Requirements for Stainless Steel Bars, Billets, and Forgings
- ASTM A582 / A582M-Standard Specification for Free-Machining Stainless Steel Bars
Stainless Steel Bar Conditions
- Condition A—Annealed
- Condition H—Hardened and tempered at a relatively low temperature
- Condition T—Hardened and tempered at a relatively high temperature
- Condition S—Strain Hardened—Relatively light cold work
- Condition B—Relatively severe cold work
Stainless Steel Grades
Stainless steel grades are available for bars which include Austenitic, Austenitic-ferritic (Duplex), Ferritic, and Martensitic grades, these grades have specific properties applied in specific applications, commonly stainless steel includes 304/304L, 316/316L, 321, 347 and 400 series grades, with multiple surface finish options.
| Stainless Steel Grades | Chemical Composition % By Mass Max Unless Stated | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| UNS No | AISI No. | C | Si | Mn | P | S | Cr | Mo | Ni | Others |
| S30400 A276 For Bar | 304 | 0.08 | 1.00 | 2.00 | 0.045 | 0.030 | 18.0/20.0 | 8.0/11.0 | ||
| S30403 A276 For Bar | 304L | 0.030 | 1.00 | 2.00 | 0.045 | 0.030 | 18.0/20.0 | 8.0/12.0 | ||
| S31600 | 316 | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 16.0/18.0 | 2.00/3.00 | 10.0/14.0 | N 0.10 |
| S31603 | 316L | 0.030 | 0.75 | 2.00 | 0.045 | 0.030 | 16.0/18.0 | 2.00/3.00 | 10.0/14.0 | N 0.10 |
| S31635 | 316Ti | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 16.0/18.0 | 2.00/3.00 | 10.0/14.0 | Ti 5x (C+N) / 0.70 N 0.10 |
| S31700 | 317 | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 18.0/20.0 | 3.0/4.0 | 11.0/15.0 | N 0.10 |
| S31703 | 317L | 0.030 | 0.75 | 2.00 | 0.045 | 0.030 | 18.0/20.0 | 3.00/4.00 | 11.0/15.0 | N 0.10 |
| S32100 | 321 | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 17.0/19.0 | – | 9.0/12.0 | Ti 5 X C Min/0.70 N 0.10 |
| S34700 | 347 | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 17.0/19.0 | – | 9.0/13.0 | Nb+Ta 10 X C Min/1.0 |
200 Series – Chromium-Nickel-Manganese Austenitic Stainless Steels
300 Series-Chromium-Nickel Austenitic Stainless Steels
301 – Good ductility, used for formed products. It can also be hardened by machine speed. Good weldability. Wear resistance and fatigue strength superior to 304 stainless steel.
302 – Corrosion resistance is the same as 304, with relatively high carbon content for better strength.
303- By adding a small amount of sulfur and phosphorus to make it better for cutting and machining.
304– i.e. 18/8 stainless steel. GB grade 06Cr19Ni10.
309– Has better temperature resistance than 304.
316 – After 304, the second most widely used steel grade, mainly used in the food industry and surgical equipment, with the addition of molybdenum to obtain a special corrosion-resistant structure. It is also used as a “marine steel” due to its better resistance to chloride corrosion than 304, while SS316 is commonly used in nuclear fuel recovery devices. 18/10 grade stainless steel is also widely used in this application.
18/10 grade also typically meets this application level.
321 – Similar properties to 304 except that the addition of titanium reduces the risk of corrosion in the weld seams of the material.
400 Series – Ferritic and Martensitic Stainless Steels
408-Good heat resistance, weak corrosion resistance, 11% Cr, 8% Ni.
409 – The cheapest type, usually used as automotive exhaust pipes, is ferritic stainless steel (chromium steel).
410 – Martensitic (high-strength chromium steel), good wear resistance, poor corrosion resistance.
416 – Sulfur is added to improve the machinability of the material.
420 – Cutting tool grade” martensitic steel, similar to Brinell high-chromium steel, the earliest stainless steel. Also used for surgical knives and can be made very bright.
430 – Ferritic stainless steel, decorative, e.g. for car accessories. Good formability, but temperature and corrosion resistance are poor.
440 – high strength cutting edge steel, slightly higher carbon content, after appropriate heat treatment can obtain high yield strength, hardness can reach 58HRC, belong to the hardest stainless steel. The most common application example is “razor blades”. There are three commonly used grades: 440A, 440B, 440C, and 440F (easy-to-machine).
500 Series – Heat-resistant chromium alloy steel.
600 Series – Martensitic precipitation-hardening stainless steel.
630-The most common type of precipitation-hardening stainless steel, often called 17-4; 17% Cr, 4% Ni.
Stainless Steel Bar Shapes And Types
Stainless steel sizes range from 5 mm to 500 mm, the length can be random or cut into fixed lengths, we offer tight sizes and dimensions for stainless steel bars, and there are several shapes for options, round bar, square bar, hexagon bar, flat bar, we have large stainless steel bar stock and various size for option.
Stainless Steel Bar Sizes
- The specification of round bar ranges from 1mm to 480mm.
- The specification of square bar ranges from 33 to 100 mm.
- Hexagonal bars range from S=4mm to S=55mm.
Stainless Steel Bar Tolerances
Stainless steel bar permitted variations in size should be in accordance with standards, the tolerances are stated in ASTM A484 specification, cold finished and hot finished bar tolerances are separately shown, there are also different shapes on different tolerance, like the round bar, square bar, hex bar, and flat bar, cold finished round bar tolerances are shown below.
| Size Tolerances – Cold Finished Round Bars – A484 | ||
|---|---|---|
| Specified Sizes Inches (Mm) | Over In. (Mm) | Under In. (Mm) |
| .1/16 To 5/16” (1.5 To 8.00), Excl | 0.001 (0.03) | 0.001 (0.03) |
| 5/16” To 1/2” (8.0 To 13.0) Excl | 0.0015 (0.04) | 0.0015 (0.04) |
| 1/2 To 1” (13.0 To 25.0) Excl | 0.002 (0.05) | 0.002 (0.05) |
| 1” To 1-1/2” (25.0 Tp 38.0) Excl | 0.0025 (0.06) | 0.0025 (0.06) |
| 1-1/2” To 3-1/4” (38.0 To 83.0) Excl | 0.003 (0.08) | 0.003 (0.08) |
| 3-1/4” T O4” (83.0 To 100) Excl | 0.005 (0.13) | 0.005 (0.13) |
Manufacture And Conditions
Cold finishing is a common method for stainless steel bars, made from stainless steel plates or strips, cold forming and extrusion, then a cold drawn and annealed process is carried out, making the bar surface bright and smooth, a polishing service is available.
- hot worked
- hot worked and annealed
- hot worked, annealed and cold worked
- hot worked, annealed, and heat-treated
Stainless Steel Bar Applications
Stainless steel bar has a broad application prospect, and are widely used in hardware kitchenware, shipbuilding, petrochemical, machinery, medicine, food, electricity, energy, building decoration, nuclear power, aerospace, military and other industries! Equipment used in seawater, chemical, dyestuff, paper, oxalic acid, fertilizer and other production equipment; food industry, coastal area facilities, ropes, CD rods, bolts, and nuts. Quality management: ISO9001:2000 quality management system certification, production license, etc.
Remarks: We can make non-standard customized stainless steel bars of various materials and specifications.