Indian Journal of Engineering

Home

Volume 23, Issue 60, July - December, 2026

Effect of Microstructure on the Oxidation Behavior and Thermal Shock Resistance of Ti-17 Alloy

Eman S Obaid, Ekbal Mohammed Saeed Salih, Saad Hameed Al-Shafaie

College of Materials Engineering, University of Babylon, Iraq

ABSTRACT

The microstructure features of Ti-17 titanium alloy are very important to its mechanical properties and high-temperature life. In this work, the effect of compositional changes on the microstructure, hardness and oxidation resistance and thermal shock behavior of Ti-17 alloys was thoroughly studied. Seven compositions of Ti-17 alloy with various concentrations of Al, Mo, Cr and Zr were successfully produced by powder metallurgy by powder mixing, cold compaction and argon shielded sintering at 1500°C. The fabricated alloys were characterized by X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX), Brinell hardness testing, high-temperature oxidation tests at 600, 700 and 800°C, and thermal shock tests at 600 and 700°C. The findings showed that changes in the amounts of the alloying elements had a considerable effect on the balance of the α/β phases and therefore on the mechanical and thermal characteristics. Alloy No. 4(82Ti-2Sn-2Zr-5Al- 5Mo-4Cr) had the best overall performance of 402 HB, which was about 2.3% higher than the typical Ti-17 alloy (396 HB). The alloy also displayed the lowest oxidation weight increase at 800°C, suggesting better oxidation resistance owing to the creation of a stable and adherent protective oxide layer and simultaneously the strongest resilience to thermal shock under cyclic heating and cooling circumstances. The better performance was due to the optimal balance of α- and β-phase stabilizing elements, which resulted in a finer microstructure and improved oxide-scale stability. These results demonstrate that the controlled compositional optimization of Ti-17 alloys prepared by powder metallurgy is an effective strategy to enhance hardness, oxidation resistance and thermal shock resistance simultaneously, which makes the optimized alloy a promising candidate for high-temperature aerospace and advanced engineering applications.

Keywords: Ti-17, Oxidation, Thermal Shock, Microstructure