Ti-5Al-5V-5Mo-3Cr metastable beta titanium alloy was prepared by rapid thermomechanical powder consolidation approach from blended elemental powder mixture. Allotropic phase transformation and high-temperature tensile behaviour of the consolidated powder metallurgy Ti-5553 alloy were investigated in this work. The studied alloy has a high β phase transformation temperature of 975 °C±5 °C, which is higher than other conventional ingot metallurgy Ti-5553 alloys. The β grains in the microstructure of the alloy are coarsened significantly with increasing the heating temperature from 890 °C to 1050 °C, however, the grain coarsening tendency is mitigated when the heat treatment temperature reach to the range of 1080 °C–1100 °C. The high-temperature tensile mechanical properties of the alloy are sensitive to both the deformation temperature and strain rate, and superplastic deformation of the alloy was achieved at the condition of 850 °C/0.001 s⁻¹ with the tensile elongation of 103.5%. The microstructural evolution characteristics and the fracture mechanisms of the alloy are varied with changing the deformation variables, which are revealed by the microstructure observation of the fractured specimens from different sampling positions.

通过快速热机械粉末固结法，从混合的元素粉末混合物中制备了Ti-5Al-5V-5Mo-3Cr亚稳β钛合金。研究了固结粉末冶金Ti-5553合金的同素异相转变和高温拉伸行为。所研究的合金具有975°C±5°C的高β相变温度，高于其他传统的锭冶金Ti-5553合金。随着加热温度从890°C升高到1050°C，合金微观结构中的β晶粒显着粗化，但是，当热处理温度达到1080°C–1100°时，晶粒粗化趋势得到缓解。 C。^-1，拉伸伸长率为103.5％。合金的显微组织演变特征和断裂机理随着变形变量的变化而变化，这通过从不同取样位置对断裂试样的显微组织观察可以看出。