Mathabathe, Maria NtsoakiBolokang, A.S.Govender, G.Siyasiya, Charles WitnessMostert, Roelf Johannes2022-05-062022-05-062021-04Mathabathe, M.N., Bolokang, A.S., Govender, G., Siyasiya, C.W., and Mostert, R.J. 2021 Deformation and fracture behaviour of the g-TiAl based intermetallic alloys. Journal of the Southern African Institute of Mining and Metallurgy, vol. 121, no. 4, pp. 169–174. DOI ID: http://dx.DOI.org/10.17159/2411-9717/1344/2021.0038-223X (print)2225-6253 (online)10.17159/2411-9717/1344/2021https://repository.up.ac.za/handle/2263/85120The b-solidifying g-TiAl intermetallic alloys of nominal composition Ti-48Al (binary alloy), Ti-48Al-2Nb (ternary alloy), Ti-48Al-2Nb-0.7Cr (quaternary alloy), and Ti-48Al-2Nb-0.7Cr-0.3Si (quinary alloy) (in at.%) were developed. The materials produced were tensile tested at room temperature. The as-cast microstructures and fracture surfaces of the tensile tested specimens were examined using conventional metallographic methods. Microstructural examination indicated that the alloys were comprised of lamellar structures (a2+g) embedded in columnar dendritic cores in the as-cast condition. However, the quinary alloy contained a Ti5Si3 second phase. The alloys exhibited no detectable ductility during tensile deformation, indicating the brittleness of all the materials. The fracture surfaces revealed that the alloys failed by translamellar fracture with correspondingly few cleavage facets.en© The Southern African Institute of Mining and Metallurgy, 2021g-TiAl based alloysb-SolidifyingTranslamellar fractureEngineering, built environment and information technology articles SDG-09SDG-09: Industry, innovation and infrastructureEngineering, built environment and information technology articles SDG-12SDG-12: Responsible consumption and productionArticle