The methods of optical and electron microscopy are used to study the relation between the processes of scale formation and propagation of surface cracks in TiAl alloys under heat treatment. It is shown that cracks propagate during post-treatment cooling in the oxide layer on the surface of the alloy, and the probability of their formation decreases in the case of tight adhesion of the scale to the metal due to enhancement of the surface smoothens. Control of the thickness of the scale formed in cooling of the alloy and its removal are important factors for preventing surface cracks arising in the heat treatment of the TiAl alloy.
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Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 8, pp. 13 – 17, August, 2021.
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Yang, H., Jung, WC., Lee, C. et al. Effect of Surface Smoothness on the Structure of Scale and Formation of Surface Cracks in TiAl Alloys under Heat Treatment. Met Sci Heat Treat 63, 414–418 (2021). https://doi.org/10.1007/s11041-021-00704-7
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DOI: https://doi.org/10.1007/s11041-021-00704-7