Experimental investigation on the effect of equal channel angular pressing on the mechanical wear and corrosion properties of al tib2 in situ metal matrix composite

Abstract

Particle-reinforced metal-matrix-composites (PRMMCs) are suitable for critical applications in aerospace, automotive and sports industries. PRMMCs have very good wear, corrosion and thermal resistance with low density. In recent times, PRMMCs have been fabricated through in-situ techniques instead of the conventional ex-situ techniques. The in-situ methods are capable of producing finer particles with a clean interface at the particle and matrix region. However, the ceramic particles tend to agglomerate in the newlinematrix during solidification, which adversely affects the mechanical properties of the PRMMCs. Therefore, secondary processing methods like forging, extrusion and rolling are used to achieve better particle dispersion in the matrix materials. In recent years, severe plastic deformation (SPD) techniques have been employed to produce an ultrafine grained (UFG) and nano-grained structure in the matrix materials, which improves the strength and toughness of the materials simultaneously. In the present study, AA6061-5wt.%TiB2 PRMMCs have been fabricated through in-situ salt-melt reaction, using potassium hexafluorotitanate (K2TiF6) and potassium tetrafluoroborate (KBF4) precursors. The annealed AA6061-TiB2 composite and AA6061 samples were subjected to equal channel angular pressing (ECAP) up to 10 passes at ~300 °C (0.45and#1050422;and#1051616; - melting temperature). The scanning electron microscope (SEM) was used to identify the particle distribution in the aluminum matrix materials. Transmission Electron Microscopy (TEM) was used to examine the grains and precipitates. newline newline