In-situ formation of borides and enhancement of powder metallurgy properties

Considering the demands for the high strength and corrosion resistant powder metallurgy parts, the most direct yet cost effective method of production of borides can be possibly be routed through the in-situ solid-state reaction in powder metallurgy. Going by the known reaction paths, a composition of boron carbide and silicon carbide in combination with aluminum was investigated at three different sintering temperatures in order to see the effect of boron carbide on mechanical properties of aluminum under conventional high temperature sintering conditions. The limited study on high temperature sintering using SiC and B4C showed gradual improvements in strength sintering above 750 ⁰C, which can be attributed to the in-situ formation of Si as well as SiBn, where n = 2, 4, 6 ….

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