For manufacturers and builders in Hamilton and beyond who demand durability and reliability, Latham Steel is a trusted local source for precision-engineered alloy steel 4140 fasteners. We understand that the success of your project, from a heavy-duty piece of machinery to critical infrastructure, hinges on the quality of its smallest components. That’s why we supply bolts, nuts, and studs crafted from this exceptional chromium-molybdenum steel, offering a superior blend of strength and toughness that stands up to the most demanding Kiwi working conditions.
The exceptional performance of 4140 alloy steel stems from its carefully balanced composition, primarily iron with key additions of chromium and molybdenum. This blend allows the steel to be heat-treated to achieve remarkable mechanical properties, resulting in fasteners with a high tensile strength and excellent wear resistance. They offer a great balance, being hard enough to resist deformation under heavy loads while maintaining a necessary degree of toughness to withstand impact and shock without becoming brittle.
| Standard | ASTM A193, ASTM A194 / ASME SA193, SA194 GR, IS, BS |
| Specification | IS, BS, ASTM |
| Size | M 02 to M 160 |
| Length | UPTO 5 METERS |
| Grade | B 6, B 7/ B 7M, B 16, 2, 2HM, 2H, GR 6, B 7, B 7M |
| Type | Bolts, nuts, Washers, Anchor Fasteners, Stud Bolts, Eye Bolt, Stud, Threaded Rod, Cotter Pin, Socket Screw, Fine Fasteners & Spares, Foundation Fasteners, etc. |
| Element | AISI 4140 |
| Fe | 96.785 – 97.77 |
| Cr | 0.80 – 1.10 |
| Mn | 0.75 – 1.0 |
| C | 0.380 – 0.430 |
| Si | 0.15 – 0.30 |
| Mo | 0.15 – 0.25 |
| S | 0.040 |
| P | 0.035 |
| Grade AISI 4140 | Metric | Imperial |
| Tensile strength | 655 MPa | 95000 psi |
| Yield strength | 415 MPa | 60200 psi |
| Bulk modulus (Typical for steel) | 140 GPa | 20300 ksi |
| Shear modulus (typical for steel) | 80 GPa | 11600 ksi |
| Elastic modulus | 190-210 GPa | 27557-30458 ksi |
| Poisson’s ratio | 0.27-0.30 | 0.27-0.30 |
| Elongation at break (in 50 mm) | 25.70% | 25.70% |
| Hardness, Brinell | 197 | 197 |
| Hardness, Knoop (converted from Brinell hardness) | 219 | 219 |
| Hardness, Rockwell B (converted from Brinell hardness) | 92 | 92 |
| Hardness, Rockwell C (Converted from Brinell hardness, value below normal HRC range, for comparison purposes only.) | 13 | 13 |
| Hardness, Vickers (converted from Brinell hardness) | 207 | 207 |
| Machinability (Annealed and cold drawn. Based on 100% machinability for AISI 1212 steel.) | 65 | 65 |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
| Grade AISI 4140 | Metric | Imperial |
| Thermal expansion co-efficient (@ 0-100°C/32-212°F) | 12.2 µm/m°C | 6.78 µin/in°F |
| Thermal conductivity (100°C) | 42.6 W/mK | 296 BTU in/hr.ft².°F |
You’ll find our 4140 fasteners are the go-to choice in situations where ordinary steel simply wouldn’t hold up. They are indispensable in high-stress environments like heavy machinery, mining equipment, and automotive suspensions where components face constant vibration and shock loads. They are also perfect for constructing robust jigs and fixtures, in demanding agricultural machinery, and within the oil and gas industry. Essentially, any application that requires a fastener that can take a serious pounding without failing is a perfect job for 4140.
Latham 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 Hamilton, New Zealand.
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