DEVELOPMENT OF LOW ALLOY STEEL BY P/M ROUTE

Abstract

The BrOw-th of the powder metUtwgy industry had been. based !irrily on 'its ability to produce intricate shapes and close tolerances with a maximum of material utilization, It should be GnXha$jZO4 that there is hardly any, area in powder metallurgy as fascinating and attracting as much attention as PM orging or hot forming, The present investigation deals with the hot forging Of premixed encased powders in a semi closed die at a protective dissociated ammonia atmosphere, Hot forging wan carried out at 1iO°C on electrolytic iron power.0 O.4%c steel. powder and on alloy steel (EN.19 powder iixture, brittle fracture was observed on all, of the fractured tensilE apeoiwns# Tensile strengths were found to be of lower Value* Charpy teat carried out on electrolytic iron specime (without notch) resulted in high impact strength (13,2 kgim), The fracture was ductile* Hovewry results of notched spec were not Sati aot, Brittle fracture was observed on then notched specimens, Lower hardness Values were reported from aU these specimens, These results show that the metal powde • was not fully compacted* BrittlMOSS observed in these eampi may also be due to some ufldisscjate4 amionio reacted with the sample ,