INFLUENCE OF ALLOYING ELEMENTS ON MECHANICAL-PROPERTIES OF SINTERED HIGH-SPEED STEEL POWDERS DILUTED WITH HIGHLY COMPRESSIBLE POWDERS

The influence of carbon and nickel on the mechanical properties of hig h speed steel (HSS) powders diluted with a highly compressible powder (e.g. pure iron or low alloy steel powder 4401) has been investigated. The aim was to optimise the mechanical properties and microstructure in the sintered steel which is used for wear resistant applications. T he results show that the carbon content is a critical factor in determ ining the mechanical properties and the amount of retained austenite i n the sintered steel. Nickel additives enhance mechanical properties a nd do not significantly affect the amount of retained austenite at con tents lower than 2%. The 4401 low alloy steel is a more suitable matri x than pure iron in this respect. The influence of retained austenite on the microhardness of the prior HSS particles does not show any dire ct relationship with the mechanical properties of the sintered composi te. (C) 1995 The Institute of Materials.