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This study explores the effects of excess Al and annealing at high temperature on the purity of Ti3AlC2 MAX phase synthesized by the mechanochemical route. In this regard, a constant stoichiometric ratio of Ti: Al: C = 3: 1: 2 along with three blends of nonstoichiometric ratios with excess Al (Ti: Al: C = 3: X: 2, X = 1.1, 1.2, and 1.5) were ball milled. Then, to examine the annealing at high‐temperature effects, the compacted ball‐milled powders were heated at 900 and 1200°C for 1 h. The phase identification revealed that 10 h of ball milling caused a reaction between the elemental powders, and Ti3AlC2 and TiC were formed. The mechanism of the reaction during the high‐energy ball milling process is assigned to a mechanically induced self‐propagating reaction. Addition of excess Al to primary powders caused to increase the purity of Ti3AlC2 significantly. Furthermore, annealing at high temperature leading to complete reactions of the ball‐milled powders and increased Ti3AlC2 purity. The maximum Ti3AlC2 content of 88% was obtained of initial powder of Ti: Al: C = 3: 1.2: 2 ratio after annealing at 1200°C. [ABSTRACT FROM AUTHOR]

In this research work, wear characteristics of the Al2024 alloy exposed to friction stir processing (FSP) with/without addition of the Ti2SC MAX phase have been investigated. Microstructural investigations revealed a good correlation between SZ and base alloy, and no defects such as cracks, etc. were detected. SEM micrographs confirmed the uniform dispersion of the Ti2SC particles in the Al2024 matrix after FSP. Also, redistribution of the precipitates of Al2024 alloy was observed. A decrease in the hardness of the 3-pass FSPed specimen without Ti2SC was observed due to the grain size increase and coarsening of the precipitates. The considerable improvement in wear rate and friction coefficient was realised by adding the Ti2SC MAX phase in the base alloy. Abrasive abrasion properties such as ploughing, plastic deformation, and grooves on surfaces indicate abrasive abrasion is the predominant wear mechanism for all specimens. [ABSTRACT FROM AUTHOR]