Development of innovative MAX phase bond coats for thermal barrier coatings using multi-scale simulations

초록

Thermal barrier coatings (TBCs) can face significant thermal and residual stress, particularly at high temperatures. To address this challenge, bond coats (BCs) are needed that can effectively mitigate these stresses. This work designs innovative MAX phase (Cr2AlC, Mo2AlC, and W2AlC) BCs with the aim of enhancing thermal shock and crack resistance using multi-scale simulations. The results show Mo2AlC to be particularly suitable as a BC due to its thermal expansion compatibility with both the thermally grown oxide (TGO, Al2O3) and the substrate, outperforming conventional metallic BCs. The small difference in CTE between the MAX phases and TGO or top coat can effectively relieve thermal stress. Also, the BC Mo2AlC with substrate IN617 has the highest flexural strength at high temperature, which has the highest crack resistance. This paper reports on the computational discovery of novel MAX phases, paving the way for the next generation of durable TBCs.

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