Microstructure and mechanical properties of Cu-12 Al-6 Ni with Ti addition prepared by powder metallurgy

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 803; p. 140472
• Main Authors: Deng, Zhenghua, Yin, Haiqing, Zhang, Cong, Li, Wanquan
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 28.01.2021; Elsevier BV
• Subjects: Alloy powders; Alloys; Aluminum base alloys; Coefficient of friction; Copper; Cu–Al–Ni alloy; Hardness; Mechanical properties; Microstructure; Nickel aluminides; Nickel compounds; Powder metallurgy; Self lubricating bearings; Self lubrication; Sintering (powder metallurgy); Sleeves; Tensile strength; Titanium; Trace elements; Tribological properties; Wear resistance; Mechanical properties; Cu–Al–Ni alloy; Tribological properties; Powder metallurgy; Ti
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2020.140472

Owing to its excellent wear resistance and good mechanical properties, the sintered Cu–Al–Ni alloy is an ideal material for preparing sliding bearings and self-lubricating sleeves. Adding trace elements into the Cu–Al–Ni alloy is expected to further enhance these properties. Hence, in this work, the microstructure and properties of sintered Cu-12 Al-6 Ni alloys with varying contents of added Ti are studied. Results indicated that the NiAl, γ2, and α phases were distinctly refined when the Ti addition was 0.2 wt%, and a small amount of the granular X phase ((Cu, Ni)2AlTi) appeared in the alloy. The X phase increased and coarsened with increasing Ti addition. When the Ti addition was 0.7 wt%, pores appeared in the center of the large granular X phase. With increasing Ti addition, the sintered density of the alloys gradually decreased, while the hardness and tensile strength increased first and then decreased. When the Ti addition was 0.7 wt%, the hardness reached the maximum (160 HB), while when the Ti addition was 0.2 wt%, the tensile strength reached the maximum (412.2 MPa). Moreover, the friction coefficient and wear loss of the alloy were the lowest when the Ti addition was 0.2 wt%. These findings can provide some theoretical guidance for fabricating high-performance Cu–Al–Ni powder alloys.