Borosiliciding of Fe–Ni alloys and evaluation of their resistance to abrasive wear

Abstract

X-ray diffraction analysis, Mössbauer measurements and metallographic observations were performed on borosilicide coatings grown at 850°C on Armco iron and the Fe₆₄Ni₃₆ binary alloy using a KBF₄-activated powder mixture of B₄C and Si₃N₄. The phase composition of the coatings was determined, a result allowing to show that the thermochemical treatment gives rise to iron boriding and iron siliciding reactions of different strength, depending on the treated material. The presence of Ni in the base metal allows iron-free nickel silicides to form as important components of the coating. The resistance of borosilicide coatings to abrasive wear is evaluated and discussed.