Study of microstructure evolution and properties of ZrTi/GH4169 alloys prepared by low-temperature sintering of SPS

• Published in: Materials characterization Vol. 201; p. 112918
• Main Authors: Luo, Shuyi, Luo, Junting, Kang, Qingxin, Xu, Xunhu, Wang, Guofeng
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.07.2023
• Subjects: Mechanical properties; Microstructure evolution; SPS sintering; ZrTi/GH4169 alloy; Mechanical properties; ZrTi/GH4169 alloy; Microstructure evolution; SPS sintering
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/j.matchar.2023.112918

This paper proposes a method involving low-temperature SPS for preparing ZrTi/GH4169 alloy blanks. The addition of GH4169 alloy significantly reduces the sintering temperature of ZrTi alloy. The Zr30-Ti62-Ni8 ratio was used to obtain equiaxed grains of ZrTi alloy through sintering at 1000 °C, and billets with excellent strength and plasticity under high-temperature deformation were obtained by sintering at 1100 °C. In the sintering temperature range from 1000 °C to 1200 °C, while both α-phase and Zr2(Fe,Ni) phase size increased with the sintering temperature, the amount of increase was different. Specifically, the α-phase in the alloy blanks sintered at 1100 °C was fine and reticulated, whereas that sintered at 1200 °C developed into a slatted structure. Strengthening mechanism analysis showed that the strength and plasticity of the 1100 °C sintered blanks were excellent, especially because of the effect of the reticulated α-phase and Zr2(Fe,Ni) phase. Furthermore, the high density of the phase interface hindered dislocation movement and inhibited stress concentration. In particular, the Zr2(Fe,Ni) phase distributed along the β-phase grain boundaries and around the α-phase in the grain acted as a nail, and it could inhibit grain growth and increase resistance to dislocation motion. The weaker β-phase weave and lower defect density also contributed to the superior material properties of the 1100 °C sintered blanks. •This paper proposes a method involving low-temperature SPS for preparing ZrTi/GH4169 alloy blanks.•Zr30-Ti62-Ni8 blanks with excellent strength and plasticity under high temperature deformation were obtained by sintering at 1000°C–1200 °C.•4) The weaker β-phase weave and lower defect density were also responsible for the superior material properties in the case of sintering at 1100 °C.