摘要 |
A sintered steel and a method for the manufacture thereof are described, the sintered steel being made by a method comprising the steps of providing a first pre-alloyed steel powder having a composition comprising in weight %: C 0.5-2, Cr 3.5-6, (2 Mo+W) 12-22, V 0.5-5, Co 0-12, Mn 0.1-0.5, Si 0.1-0.6, Fe balance apart from incidental impurities; providing a second pre-alloyed steel powder having a composition comprising in weight %: C 0.3-0.7, Cr 3-5.5, Mo 1-2.5, V 0.3-1.5, W 0-2, Mn 0.1-0.6, Si 0.8-1.2. Fe balance apart from incidental impurities; mixing together from 2 to 50 weight % of the first pre-alloyed steel powder with 98 to 50 weight % of the second pre-alloyed steel powder optionally up to 60 weight % of an iron powder and with carbon powder such that the final carbon content of the matrix of the sintered steel powder is a maximum of 1.1 weight %1; compacting the mixture and sintering to form the sintered steel.
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