Fe-Ag pseudo-alloys obtained by wire electric explosion, ball milling and spark plasma sintering

Abstract

• Fe-Ag pseudo-alloys formed by wire electric explosion and spark plasma sintering. • WEE powder was ball-milled to improve its structural uniformity. • In pseudo-alloy formed from milled powder, silver grains were 300-500 nm in size. • Material sintered from ball-milled powder showed a higher microhardness. • Porous silver with a uniform structure was obtained from sintered material. Structural features of Fe-25 wt.% Ag pseudo-alloys obtained by spark plasma sintering of the product of wire electric explosion (WEE) and the product of WEE processed by ball milling were comparatively investigated for the first time. In the sintered pseudo-alloy produced from the WEE powder, inclusions of iron 5-10 μm were found in the Fe-Ag composite matrix. The size of silver grains was of the order of 1 μm and 300-500 nm in the sintered materials produced from the WEE powder and ball-milled powder, respectively. The pseudo-alloys sintered from the ball-milled powder showed a higher microhardness than the material sintered from the WEE powder. Porous silver obtained from the pseudo-alloy sintered from the WEE powder by selectively dissolving iron showed micrometer-sized pores in the former places of iron particles of those sizes. In contrast, porous silver obtained from the pseudo-alloy sintered from the ball-milled powder had a uniform structure free from large pores.