JFE Steel Corporation, headquartered in Tokyo, Japan, states that it has developed a nickel-free alloyed steel powder known as FM800. The new powder is said to offer 800 MPa-class tensile strength when sintered in a mesh-belt furnace, making it suitable for numerous Powder Metallurgy applications.
FM800 is an alloyed steel powder that is prealloyed with 3% copper and 1.3% molybdenum. Whereas prealloying with alloy elements can reduce the compressibility of powder, the company states that it has successfully achieved higher compressibility by controlling the production process. FM800’s advantages are expected to be utilised for the manufacture of automotive and construction equipment parts.
Conventionally, alloyed steel powder containing 4% nickel, 1.5% copper and 0.5% molybdenum is used for these parts, but not without problems. Typically, a significant drop in post-sintering hardness reduces machinability and increases processing costs, and susceptibility to fluctuations in the market price of nickel.
To address these issues, JFE Steel has been offering its FM Series of nickel-free alloyed steel powders that reportedly enable customers to enhance product quality as well as cut costs. The FM Series includes FM600, which offers 600 MPa-class tensile strength when mesh-belt sintered; FM1000, which achieves 1,000 MPa-class tensile strength after carburisation; FM1000S, which boasts extra toughness in addition to the properties of FM1000; and FM1300, which is heat-treated after high-temperature sintering to achieve superb tensile strength of 1,300 MPa.
According to JFE Steel, in the case of 800 MPa-class tensile strength, however, nickel-free alloyed steel powder previously had to undergo carburisation heat treatment, but the corporation’s development team has been able to eliminate this step to help customers reduce costs. JFE Steel is believed to be Japan’s only manufacturer of a total range of iron powders, including reduced-iron powder, atomised-iron powder and alloyed-steel powder.