LAUSR

Abstract Ti2AlC and Ti3AlC2 coatings were successfully prepared via a two-step method with initial DC magnetron sputtering at ambient temperature and post annealing at 800 °C for 1 h. Particularly, cost-effective targets synthesized by hot-pressing Ti/Al/C powders at low temperature (800 °C) were used. The phase components and microstructure of the coatings were characterized by XRD, laser Raman spectroscopy, SEM and TEM. It was found that the phase components of the as-deposited and annealed coatings varied with the molar ratio of Ti, Al and C powders in the cost-effective targets. Phase-pure Ti2AlC and Ti3AlC2 could be obtained from the target with the Ti:Al:C molar ratios of 2:1.5:1 and 3:2:2, respectively. These two coatings were consisted of plate-like grains. Due to the high internal stress resulting from crystallization- or phase transformation-induced volume change, both of the Ti2AlC and Ti3AlC2 coatings cracked during the annealing process.