High density sintered ferrous alloys

A powder mixture comprising an atomized copper-free ferrous alloy powder and copper phosphide powder, which mixture when compressed and sintered provides a sintered ferrous alloy consisting essentially of, in percentages by weight:

• ______________________________________ carbon 0.6-2.5% chromium 2-8% copper 4.5-20% molybdenum 0.5-10% phosphorus 0.4-1.2% tungsten 1-20% vanadium 1-5% cobalt 0-12% manganese 0-2% nickel 0-2% ______________________________________
• the balance being iron and less than 2% by weight impurities, wherein the molybdenum, tungsten and vanadium contents are such that the % carbon content is in the range CCC%-0.1% to CCC%+0.3%, where CCC% is the calculated carbon content= (CWE/20)-0.4 and CWE=%tungsten content+twice % molybdenum content+six times % vanadium content, and wherein the copper phosphide contains 2to 14% phosphorus.

A process of manufacturing a sintered alloy article, which process comprises mixing atomized copper-free ferrous alloy powder and copper phosphide powder, compressing the powder mixture into a shaped article and sintering said article, wherein the powder mixture when compressed and sintered provides a sintered ferrous alloy consisting essentially of, in percentages by weight:

• ______________________________________ carbon 0.6-2.5% chromium 2-8% copper 4.5-20% molybdenum 0.5-10% phosphorus 0.4-1.2% tungsten 1-20% vanadium 1-5% cobalt 0-12% manganese 0-2% nickel 0-2% ______________________________________
• the balance being iron and less than 2% by weight impurities, wherein the molybdenum, tungsten and vanadium contents are such that the % carbon is in the range CCC%-0.1% to CCC%+0.3%, where CCC% is the calculated carbon content=(CWE/20)-0.4 and CWE=% tungsten content+twice % molybdenum content+six times % vanadium content, and wherein the copper phosphide contains 2 to 14% phosphorus.