Travis Steel, located in Canberra, Australia, stands out as a top manufacturer and supplier of high-quality Alloy Steel AISI 4340 Bars. These bars are well-known for their remarkable strength, toughness, and resistance to fatigue. The company specializes in crafting precision-engineered bars that adhere to strict international quality standards, catering to essential industries like aerospace, automotive, oil and gas, and heavy engineering. Designed for demanding applications, Travis Steel’s AISI 4340 Bars excel under extreme stress and fluctuating temperatures. Thanks to advanced manufacturing techniques and thorough quality control, these bars guarantee consistent mechanical properties, durability, and a long service life, making them perfect for high-stress and safety-critical industrial uses.
Alloy Steel AISI 4340 Bar is a low-alloy steel enriched with nickel, chromium, and molybdenum, containing about 0.38–0.43% carbon, 0.60–0.80% chromium, 0.20–0.30% molybdenum, 0.70–0.90% nickel, and 0.60–0.80% manganese. This unique blend offers exceptional hardenability, impressive tensile strength, toughness, and fatigue resistance. In terms of mechanics, AISI 4340 Bars deliver high yield and ultimate strength, outstanding impact resistance, and good ductility, all while maintaining dimensional stability in high-stress and high-temperature environments. The material also responds favorably to heat treatment, boosting surface hardness while keeping a resilient core.
| Sizes | 2-100mm A/F |
|---|---|
| Tolerance | H9, H8, H10, K12, H13K9, K10, H11, H12, K11 |
| Round bar Sizes | Diameter: 3-~800mm |
| Technique | Hot Rolled, Cold Drawn, Cold Rolled, Forged, Rod |
| Processing | Bar cutting to 650mm |
| Surface | Bright, Hot Rolled Pickled, Sand Blasting Finished, Hairline, Cold Drawn, Polished suppliers |
| Condition | Hardened and tempered, annealed |
| Form | Precision Square, Ingot, T-Bar, Rod, Round, Welding Rod, I/H Bar, Flat Bar, Blocks, Rings, Rectangle, Hex (A/F), Hollow, Threaded, Profiles, Ground Bar, Channel Bar, Billet, Triangle, Round Rod, Half Round Bar, Forging etc. |
| Square bar Sizes | 4 to 100mm |
| Finish | Hot rolled annealed, Bright, smooth turned, Polish, Rough Turned, Cold (bright) drawn, centreless ground, Grinding, peeled, hot rolled, slit rolled edge, Centreless Ground & Black. |
| Flat bar Sizes | Width: 10 – 500 millimeter Thick.: 2 to 100 millimeter |
| C | Mn | Si | S | P | Cr | Ni | Mo | |
| SAE – 4340 | .38- .43 | .60 – .80 | .15 – .35 | .035 MAX | .040 MAX | .70 – .90 | 1.65 -2.00 | .20 – .30 |
| Tensile strength kgf/mm² | Yield strength kgf/mm² | Elongation % | Cross section reduction rate % | Impact value | Hardness Hb |
|---|---|---|---|---|---|
| ≧100 | ≧90 | ≧16 | ≧45 | ≧7 | 293~352 |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
| SIZE IN INCHES | ROUND | SQUARE | OCTAGON | HEXAGON | SIZE IN INCHES | ROUND | SQUARE | OCTAGON | HEXAGON |
| 1/16 | .010 | .013 | .011 | .012 | 11/16 | 1.262 | 1.607 | 1.333 | 1.392 |
| 5/64 | .017 | .022 | .018 | .019 | 45/64 | 1.320 | 1.681 | 1.394 | 1.456 |
| 3/32 | .023 | .029 | .024 | .025 | 23/32 | 1.380 | 1.756 | 1.487 | 1.521 |
| 7/64 | .031 | .039 | .033 | .034 | 47/64 | 1.440 | 1.834 | 1.521 | 1.588 |
| 1/8 | .042 | .053 | .044 | .046 | 3/4 | 1.502 | 1.913 | 1.586 | 1.656 |
| 9/64 | .053 | .067 | .056 | .058 | 25/32 | 1.630 | 2.075 | 1.721 | 1.797 |
| 5/32 | .065 | .083 | .069 | .072 | 13/16 | 1.763 | 2.245 | 1.862 | 1.944 |
| 11/64 | .079 | .100 | .083 | .087 | 27/32 | 1.901 | 2.421 | 2.008 | 2.096 |
| 3/16 | .094 | .120 | .099 | .104 | 7/8 | 2.045 | 2.603 | 2.159 | 2.254 |
| 13/64 | .110 | .140 | .116 | .121 | 29/32 | 2.193 | 2.792 | 2.316 | 2.418 |
| 7/32 | .128 | .163 | .135 | .141 | 15/16 | 2.347 | 2.988 | 2.479 | 2.588 |
| 15/64 | .147 | .187 | .155 | .162 | 31/32 | 2.506 | 3.191 | 2.646 | 2.763 |
| 1/4 | .167 | .213 | .176 | .184 | 1 | 2.670 | 3.400 | 2.820 | 2.945 |
|---|---|---|---|---|---|---|---|---|---|
| 17/64 | .188 | .240 | .199 | .207 | 1-1/16 | 3.015 | 3.838 | 3.183 | 3.324 |
| 9/32 | .211 | .269 | .223 | .233 | 1-1/8 | 3.380 | 4.303 | 3.569 | 3.727 |
| 19/64 | .235 | .300 | .248 | .259 | 1-3/16 | 3.766 | 4.795 | 3.977 | 4.152 |
| 5/16 | .261 | .332 | .275 | .288 | 1-1/4 | 4.172 | 5.313 | 4.407 | 4.601 |
| 21/64 | .288 | .360 | .304 | .318 | 1-5/16 | 4.600 | 5.857 | 4.858 | 5.072 |
| 11/32 | .316 | .402 | .334 | .348 | 1-3/8 | 5.049 | 6.428 | 5.332 | 5.567 |
| 23/64 | .345 | .439 | .364 | .381 | 1-7/16 | 5.518 | 7.026 | 5.827 | 6.085 |
| 3/8 | .376 | .478 | .397 | .414 | 1-1/2 | 6.008 | 7.650 | 6.345 | 6.625 |
| 25/64 | .408 | .519 | .431 | .450 | 1-9/16 | 6.519 | 8.301 | 6.885 | 7.189 |
| 13/32 | .441 | .561 | .466 | .486 | 1-5/8 | 7.051 | 8.978 | 7.446 | 7.775 |
| 27/64 | .475 | .605 | .502 | .524 | 1-11/16 | 7.604 | 9.682 | 8.030 | 8.385 |
| 7/16 | .511 | .651 | .540 | .564 | 1-3/4 | 8.178 | 10.41 | 8.634 | 9.018 |
| 29/64 | .548 | .698 | .579 | .604 | 1-13/16 | 8.773 | 11.17 | 9.265 | 9.673 |
| 15/32 | .587 | .747 | .620 | .647 | 1-7/8 | 9.388 | 11.95 | 9.911 | 10.35 |
| 31/64 | .627 | .798 | .662 | .692 | 1-15/16 | 10.02 | 12.76 | 10.58 | 11.05 |
| 1/2 | .668 | .850 | .705 | .736 | 2 | 10.68 | 13.60 | 11.28 | 11.78 |
| 33/64 | .710 | .904 | .750 | .783 | 2-1/16 | 11.36 | 14.46 | 11.99 | 12.53 |
| 17/32 | .754 | .960 | .796 | .831 | 2-1/8 | 12.06 | 15.35 | 12.73 | 13.30 |
| 35/64 | .799 | 1.017 | .844 | .881 | 2-3/16 | 12.78 | 16.27 | 13.49 | 14.09 |
| 9/16 | .845 | 1.076 | .892 | .932 | 2-1/4 | 13.52 | 17.21 | 14.27 | 14.91 |
| 37/64 | .893 | 1.136 | .943 | .985 | 2-5/16 | 14.28 | 18.18 | 15.08 | 15.75 |
| 19/32 | .941 | 1.199 | .994 | 1.038 | 2-3/8 | 15.06 | 19.18 | 15.91 | 16.61 |
| 39/64 | .992 | 1.263 | 1.048 | 1.094 | 2-7/16 | 15.87 | 20.20 | 16.75 | 17.49 |
| 5/8 | 1.043 | 1.328 | 1.102 | 1.150 | 2-1/2 | 16.69 | 21.25 | 17.62 | 18.40 |
| 41/64 | 1.096 | 1.395 | 1.207 | 1.209 | 2-9/16 | 17.53 | 22.33 | 18.52 | 19.34 |
| 21/32 | 1.150 | 1.464 | 1.214 | 1.268 | 2-5/8 | 18.40 | 23.43 | 19.43 | 20.29 |
| 43/64 | 1.205 | 1.535 | 1.272 | 1.329 | 2-11/16 | 19.29 | 24.56 | 20.37 | 21.27 |
AISI 4340 Bars find extensive applications in the aerospace, automotive, power generation, and oil and gas sectors. They are particularly suited for crafting aircraft landing gear, crankshafts, gears, shafts, and other high-stress mechanical components that demand superior strength and toughness. Additionally, these bars are utilized in heavy machinery, industrial equipment, and tooling applications where fatigue resistance, wear resistance, and reliability are paramount. AISI 4340 Bars deliver exceptional performance even in extreme conditions, making them a go-to choice for engineering projects that require long-lasting durability and safety.
Travis Steel is a leading manufacturer, supplier and exporter of high-quality Carbon Steel, Alloy Steel, Mild Steel and Galvanized Steel products. Our extensive product range includes Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets and Plates, catering to various industries in Canberra, Australia.
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