What Is Chromium Molybdenum Steel?
Chromium Molybdenum Steel, an alloy steel, is made by adding chromium (about 1%) and molybdenum (0.15-0.3%) to carbon steel. This composition enhances the steel’s strength at high temperatures, making it a type of heat-resistant steel. The addition of molybdenum helps in reducing temper brittleness.
Applications of Chromium Molybdenum Steel
Known for its hardness, toughness, wear resistance, welding ease, and high-temperature resistance, chromium molybdenum steel is used in various machine structural components. It finds applications in automotive and aircraft parts, tools, and bicycle frames. The alloy’s resistance to embrittlement and rust, along with its surface luster and impact absorption properties, make it suitable for these uses.
Types of Chromium Molybdenum Steel
There are several types of chromium molybdenum steel, including:
- Alloy steels for machine structural use (11 types)
- Structural steels with guaranteed hardenability (8 types)
- Alloy steel pipes for machine structural use (6 types)
- Alloy steels for cold heading – Part 1 wire rod (17 types)
Specific grades like SCM435 and SCM440 are known for their high toughness, stable hardenability, and cost-effectiveness compared to nickel-chromium steels. SCM415 and SCM420 are notable for carburizing applications, offering high toughness and wear resistance.
Other specialized types include nickel chromium molybdenum steel (high toughness), aluminum chromium molybdenum steel (suitable for nitriding treatment), and high-carbon chromium-bearing steel (enhanced wear resistance).