Oxidation Behavior of MAX Phase Ti2Al(1-x)SnxC Solid Solution

MAX phase Ti2Al(1x)SnxC solid solution with x=0, 0.32, 0.57, 0.82, and 1 was synthesized by pressureless sintering of uniaxially pressed Ti, Al, Sn, and TiC powder mixtures. Annealing in air atmosphere at 200 degrees C1000 degrees C triggered a sequence of oxidation reactions which reveal a distinct influence of solid solution composition on the oxidation process. With decreasing Al/Sn ratio, the characteristic temperature of accelerated oxidation reaction of A-element was reduced from 900 degrees C (x=0) to 460 degrees C (x=1). SnO2 was formed at temperatures significantly lower than TiO2 (rutile) and Al2O3. Substitution of A-element in MAX phase solid solution by low-melting elements such as Sn may offer potential for reducing oxidation-induced crack healing temperatures.