Stability of reinforcements (CrB2/TiB2) and lubricants (C/MoS2) in Cu matrix during the sintering process
Year: 2024
Type: article
Abstract: To select suitable reinforcement and lubricant for Cu matrix and thus improve the tribological performance, the stability of widely used reinforcements and lubricants, such as CrB 2 , TiB 2 , graphite (C) and MoS 2 , in the copper matrix during sintering process was studied. The content of each reinforcement or lubricant was fixed at 10 wt%, and the powder mixture was sintered by a fast hot-pressed sintering machine at 950 °C under 40 MPa for 1 h under a vacuum atmosphere (<10 Pa). Then, microstructure and phase composition of the composites resulted from 10%CrB 2 –Cu, 10%TiB 2 –Cu, 10%MoS 2 –Cu, 10%C–Cu, 10%CrB 2 –10%C–Cu, 10%TiB 2 –10%C–Cu, 10%CrB 2 –10%MoS 2 –Cu and 10%TiB 2 –10%MoS 2 –Cu powder systems were investigated systematically, Subsequently, the potential decomposition and reaction behavior was discussed based thermodynamic analysis. Results show that single CrB 2 , TiB 2 or C phase can exist stably in copper matrix, but MoS 2 is prone to react with Cu to form Cu 2 S and Mo 2 S 3 . Both CrB 2 and TiB 2 can co-exist with C in the Cu matrix, but react with MoS 2 to form Cu 2 S, Mo 2 S 3 as well as ternary CuCrS 2 and CuTi 2 S 4 phase, since the negative Gibbs free energy change of the corresponding reaction equations. Finally, the strengthening effect of CrB 2 and TiB 2 along with the lubricating effect of graphite (C) are promise to work in Cu matrix from the viewpoint of crystal structure integrity.
Authors: Chen Zhang, Lei Jia, Jia-mei Zhang, Wu Pan, Zhen-lin Lu, Zhi-guo Xing
Institution: Xi'an University of Technology
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,430
Award: G613484139
OpenAlex ID: W4405807763