| 摘要 |
1491423 Liquid phase sintered stainless steel ALLEGHENY LUDLUM INDUSTRIES Inc 21 Jan 1976 [22 Jan 1975] 02255/76 Heading C7A A sintered stainless steel of density at least 94% of as-cast density and of composition:- C 0 to 0À05% Cr 21À4 to 26% Ni 10 to 24% Mo 2À7 to 5% B 0À1 to 1% Mn 0 to 2% Si 0 to 2% Fe plus imps balance and having a microstructure containing regions of austenitic stainless steel and regions of solidified liquid phase. The steel may be prepared by compressing a pre-alloyed stainless steel powder of the above composition at 45 tons/sq inch to form a green compact which is sintered in hydrogen or under reduced pressure (e.g. 5 x 10<SP>-2</SP> Torr) at 2250 to 2375‹F. Alternatively the powder may be admixed with 0À5% stearic acid pressed into a green compact at 45 tons/sq inch, sintered in H 2 for 30 minutes at 2000‹ to 2300‹F, re-pressed at 45 tons/sq inch and re-sintered in hydrogen for 30 minutes at 2300‹F.
|
