We manufacture forging ingots, billets, and blooms in alloy steel specifically for SAE 4142, designed for high-strength and heavy-duty engineering applications.
SAE 4142 is a medium carbon chromium-molybdenum alloy steel known for its higher carbon content compared to SAE 4140, providing increased strength, hardness, and wear resistance while maintaining good toughness and fatigue performance. It is engineered to withstand high mechanical loads, shock, and cyclic stress, making it suitable for automotive, heavy machinery, power transmission, and critical engineering components.
The addition of chromium enhances hardenability and wear resistance, while molybdenum improves toughness, tempering resistance, and high-temperature performance. SAE 4142 also offers good machinability in the annealed condition and maintains dimensional stability after heat treatment, making it highly suitable for forging and precision machining applications.
This grade provides an excellent balance of performance, durability, and cost-effectiveness for demanding industrial uses.
| Element | Content (%) | Function / effect |
| Carbon (c) | 0.40 – 0.45 | Provides higher hardness and tensile strength |
| Manganese (mn) | 0.75 – 1.00 | Improves hardenability and toughness |
| Silicon (si) | 0.15 – 0.35 | Increases strength and elasticity |
| Chromium (cr) | 0.80 – 1.10 | Enhances hardness, wear resistance, and depth of hardening |
| Molybdenum (mo) | 0.15 – 0.25 | Improves toughness, fatigue resistance, and tempering stability |
| Phosphorus (p) | Max 0.035 | Impurity; lower content improves toughness |
| Sulphur (s) | Max 0.040 | Impurity; controlled for better machinability |
(properties may vary depending on section size and heat treatment conditions)
The heat treatment process can be optimized to achieve the desired balance of strength and toughness based on specific application requirements.
SAE 4142 has several international equivalents, including:
SAE 4142 offers a superior combination of high strength, hardness, and fatigue resistance compared to SAE 4140. Its higher carbon content provides better wear performance, making it ideal for components subjected to heavy loads and cyclic stress. Additionally, its stable response to heat treatment and good machinability help improve product quality and service life.
| Grade | Carbon (%) | Key applications | Heat treatment | Comments |
| SAE 4142 | 0.40 – 0.45 | Heavy shafts, gears, crankshafts | Quenching & tempering | Higher strength than SAE 4140 |
| SAE 4140 | 0.38 – 0.43 | Shafts, gears, automotive parts | Quenching & tempering | Balanced strength and toughness |
| 42CrM04 | 0.38 – 0.45 | Heavy machinery components | Quenching & tempering | European equivalent |
SAE 4142 is a high-performance chromium-molybdenum alloy steel optimized for quench and temper applications in automotive and heavy engineering industries. It delivers reliable performance, long service life, and excellent value for high-stress and wear-critical components.