Alloy Steel 4140 Fasteners are tough, high-strength fasteners made from a chromium-molybdenum alloy steel, celebrated for its outstanding mechanical properties and reliability in tough conditions. Crafted through meticulous forging and machining, these fasteners boast uniform dimensions, a superior surface finish, and consistent performance. They meet international standards, making them perfect for critical applications in industries like automotive, aerospace, heavy machinery, and construction, where strength, toughness, and resistance to fatigue are crucial.
4140 Alloy Steel Fasteners consist of Manganese (0.75-1.0%), Chromium (0.8-1.1%), Molybdenum (0.15-0.25%), Silicon (0.15-0.30%), Carbon (0.38-0.43%), and Iron as the basic element. These fasteners possess superior mechanical properties, such as tensile strength of 850-1000 MPa, yield strength of 655 MPa, hardness of 28-32 HRC, and better impact resistance. With superior fatigue strength and toughness, 4140 fasteners excel under harsh conditions, providing durability and wear resistance. Their good machinability and heat-treatability render them suitable for applications in industry, automobiles, and structures.
| 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.
The chemical makeup of Alloy Steel 4140 Fasteners includes carbon, chromium, molybdenum, manganese, and trace amounts of silicon. This blend gives them impressive tensile strength, toughness, and wear resistance, all while ensuring good machinability and weldability. On the mechanical side, these fasteners show excellent tensile and yield strength, impact resistance, and fatigue endurance. Heat treatment processes like quenching and tempering further boost their hardness, toughness, and structural stability, guaranteeing long-lasting performance even under heavy loads and cyclic stresses.
| 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 often find Alloy Steel 4140 Fasteners in critical roles such as bolts, screws, studs, and nuts for automotive engines, industrial machinery, structural assemblies, and heavy equipment. Their unique combination of high strength, durability, and resistance to wear and fatigue makes them the go-to choice for demanding environments where safety, reliability, and a long service life are non-negotiable.
Chetak 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 Hyderabad, India.
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