In the heart of Kinshasa, Yoane Steel has built a reputation as a trusted partner for industry, providing robust solutions where they matter most. We understand the critical demands placed on machinery and infrastructure, which is why our focus on supplying high-grade Alloy Steel 4140 fasteners is more than just a product line—it’s a commitment to durability and reliability. For projects that cannot afford to fail, our bolts, nuts, and screws offer the foundational strength needed to build with confidence across the Democratic Republic of Congo.
The exceptional strength of Alloy Steel 4140 comes from a precise blend of chromium and molybdenum, giving it a remarkable toughness. These fasteners can be heat-treated to achieve a superb balance of high tensile strength and good wear resistance, allowing them to handle significant stress without fracturing. This makes them far superior to standard options, as they maintain their integrity under heavy loads and in demanding environments, providing a level of security that is essential for critical applications.
| 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 alloy fasteners at work in the most challenging scenarios, from the heavy machinery operating in local mines to the powerful engines in transportation and logging equipment. They are the preferred choice for constructing high-stress frameworks, industrial machinery, and even in the automotive sector for performance parts. Essentially, anywhere that requires a fastener that can withstand high pressure, shock loads, and repetitive stress is where the proven reliability of this alloy truly shines, ensuring long-term safety and performance.
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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