In the bustling industrial landscape of Kinshasa, Yoane Steel has established itself as a trusted partner for businesses requiring high-performance materials. We take pride in supplying robust and reliable Alloy Steel AISI 4340 bars, specifically sourced to meet the rigorous demands of the Congo’s growing engineering and manufacturing sectors. Our commitment extends beyond delivery; we provide expert support to ensure you get the exact grade and specification needed to strengthen your projects and drive local industry forward with unwavering quality.
The strength of AISI 4340 bars comes from a sophisticated composition that includes nickel, chromium, and molybdenum. This powerful combination gives the steel exceptional toughness and an impressive ability to be heat-treated to achieve very high strength levels without becoming brittle. It’s this unique balance that makes 4340 a go-to material for parts that must endure significant stress and impact, offering a resilience that few other alloys can match in such demanding environments.
| 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 |
You’ll find AISI 4340 bars at the heart of some of the most critical components in heavy machinery. They are essential for manufacturing high-strength parts like axles, crankshafts, and heavy-duty gears that power the construction and mining equipment vital to our region. Beyond this, its superior properties make it indispensable in the aerospace industry for landing gear components and in high-performance automotive applications for connecting rods and drive shafts, wherever failure is simply not an option.
Yoane 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 Kinshasa, Congo.
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