disclosed are heat resistant aluminum alloy powders and alloys including ni , si , either at least one of fe and zr or at least one of zr and ti . for instance , the alloy powders or alloys consist essentially of ni in an amount of from 5 . 7 to 20 % by weight , si in an amount of from 0 . 2 to 25 % by weight , at least one of fe in an amount of from 0 . 6 to 8 . 0 % by weight and cu in an amount of from 0 . 6 to 5 . 0 % by weight , and the balance of al . the alloy powders or alloys are optimum for a matrix of heat and wear resistant aluminum alloy - based composite materials including at least one of nitride particles and boride particles in an amount of 0 . 5 to 10 % by weight with respect to the whole composite material taken as 100 % by weight . the alloy powders , alloys and composite materials are satisfactory applicable to the component parts of the recent automobile engines which should produce a high output .