Abstract:
This study aims to investigate the effect of Gd
2Fe
17 content on the microstructure and properties of Ti
100-x(Gd
2Fe
17)
x alloys. This series of the alloys was fabricated using vacuum arc melting technology. The effects of Gd
2Fe
17 content on the microstructure and properties of the alloys were investigated by means of X-ray diffraction, scanning electron microscopy, differential thermal dilatometry and other characterization mothods. The results demonstrate that the alloys consist of β-Ti matrix and Gd-Fe intermetallic compounds(IMCs) precipitated phases. With increasing Gd
2Fe
17 content, the volume fraction of Gd-Fe IMCs in the alloys increases gradually, which leads to a continuous rise in fracture strength, and an initial increase followed by a decrease in elongation. Conversely, a gradual reduction in thermal expansion coefficient. Among all the alloys, Ti
100-x(Gd
2Fe
17)
x exhibits the optimal comprehensive performance, with a fracture strength of 774 MPa, an elongation of 7.3%, and a thermal expansion coefficient of 8.5×10
-6/℃. Compared with the Ti
98(Gd
2Fe
17)2 alloy, its fracture strength and elongation are increased by 26.5% and 40.4%, respectively, whereas its thermal expansion coefficient is decreased by 4.5%. The excellent comprehensive performance of the alloy is attributed to the strengthening and thermal expansion compensation effects of the fine, low-expansion Gd-Fe IMCs that are uniformly and dispersively distributed in the matrix.