Erosion-corrosion behavior of Ti2AlC coatings in high-speed flowing lead-bismuth eutectic

• A 6500 h erosion-corrosion test on the Ti 2 AlC coating was conducted under about 14 m/s in Lead-Bismuth Eutectic at 360℃. • The Ti 2 AlC coating peeled off in the form of strips and sheets on its surface after different periods of erosion. • The oxide layer on the coating surface , which is mainly consist of TiO 2 and Al 2 O 3 , makes the coating erosion resistant. • With the consumption of Ti and Al atoms, the coating failed after 6500 h of high-speed erosion. Long-term durability testing experiments were conducted on Ti 2 AlC coatings prepared on 316L stainless steel substrates in oxygen-saturated Lead-Bismuth Eutectic (LBE) at 360 °C for up to 6500 h with a surface flowing velocity of about 14 m/s. With prolonged erosion, stripe-like erosion traces gradually developed along the flow direction on the coating surface . O in LBE reacted with Ti and Al, leading to the formation of the protective oxide layer which was mainly composed of TiO 2 and Al 2 O 3 on the surface of Ti 2 AlC coating. The outer oxide was continuously sheared by high-speed LBE. As the Al and Ti is gradually consumed, Pb and Bi penetrate into the coating. By 6500 h, severe non-uniform thinning and accelerated spalling were observed, and some local coating had completely peeled off.