24 July 2021 Structural Steel Bar
45CrMnMo Structural Steel Bar
45CrMnMo structural steel is a structural steel with high yield strength, tensile strength and fatigue strength, as well as sufficient plasticity and toughness. Generally, electric arc furnace and oxygen top-blowing converter are used for smelting, and the demanding ones are out-furnace refining, electroslag remelting (ESR) or vacuum treatment, vacuum induction furnace smelting or double vacuum smelting, and suitable heat treatment. It is widely used in structures such as ships, vehicles, aircraft, missiles, weapons, railways, bridges, pressure vessels, and machine tools. 45CrMnMo structural steel has better mechanical properties than carbon steel, especially excellent heat treatment performance.
1. Quality performance and field of application for products
Steel for petroleum is required to have high purity, good obdurability and equal direction capacity. EX30, SN2025 steel is mainly used for roller bit of petroleum drill bits, 37CrMnMo(4137H) is used for manufacturing petroleum drill rod joint, 4145H is mainly used for petroleum drill rod and drill spindle.
2. Grade of products:
4145H(45CrMnMo) 4137H(37CrMnMo) 20CrNiMo EX30 15CrNiMo SN2025(15,MnNi4Mo) 20Ni4Mo
3. Processing route:
EAF + LF + VD + concastng steel billets + hot rolled
4. Chemical composition and mechanical properties:
| C | SI | MN | P/S | CR | NI | MO | Yield strength (MPa)
| Tensile strength (MPa)
| Elongation (%) | Reduction of area(%) | AKV | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 37CrMnMo(4137H) | 0.35-0.38 | 0.15-0.35 | 0.85-1.00 | 0.035 (MAX) | 0.9-1.2 | 0.25-0.35 | 800-1000 | 950-1100 | 13% | 54 | ||
| AISI4145H(45CrMnMo) | 0.42-0.48 | 0.15-0.30 | 0.75-1.20 | 0.035 (MAX) | 0.75-1.20 | 0.35-0.45 | 800(min) | 980 (min) | 139 min) | 54 | ||
| SN2025(15MnNi4Mo) | 0.13-0.17 | 0.15-0.35 | 0.70-0.95 | 0.035 (MAX) | 0.10-0.20 | 3.25-3.75 | 0.10-0.20 | 800(min) | 950 (min) | 10 (min) | 40 (min) | 78 |
| EX30(15CrNiMo) | 0.11-0.16 | 0.15-0.35 | 0.70-0.90 | 0.035 (MAX) | 0.45-0.65 | 0.70-1.00 | 0.45-0.65 | 750(min) | 900 (min) | 10 (min) | 40 (min) | 58 |