Heat treatment of friction surfaced steel-aluminum couple

Abstract

Friction surfacing is a solid state process and it is amenable for deposition of aluminum on steel. In this investigation, the mild steel surface was coated with a layer of aluminum using friction surfacing route. The aluminum thickness was in the range of 40-50 μm. It was followed by a heat treatment step to convert aluminum layer in to an aluminide layer. Heat treatment was done in open atmosphere at 700 °C for 2 hours. Microstuctural analysis showed that the aluminide layer is mainly made of Fe<inf>2</inf>Al<inf>5</inf> and Fe<inf>4</inf>Al<inf>13</inf>, FeAl and Fe<inf>3</inf>Al are minor in fraction. Formation of Fe<inf>2</inf>Al<inf>5</inf> is discussed. The aluminide layer also has some amount of porosities. © (2015) Trans Tech Publications, Switzerland.