Research On The Wear Behavior Of C/Cu Composites

Carbon/copper composites are widely used as electrical contact devices because of their excellent characteristics, such as good wear resistance and high electrical conductivity. The friction and wear behaviors not only depend on intrinsic characteristics of C/Cu composites, but are also decided by working system condition. The existing friction and wear testing machine and experimental results cannot fully explain the friction and wear characteristics of C/Cu composite materials. Therefore, it is of great significance to research on the wear behavior of C/Cu composites with the help of autonomously designed and produced friction and wear testing machine.The main contents of this dissertation are as follows:(1) Research on mechanism of the factors that have impact on the friction and wear characteristics of C/Cu composites. Find and study the factors affect the friction and wear characteristics of C/Cu composites, such as load, speed, water environment, materials, etc. Analysis the essential reason and predict the trend of these influences. Draw a conclusion that lubrication film plays an important role in improving the friction and wear characteristics of C/Cu composites.(2) Wear test design of C/Cu composites. Study and compare a lot of experiment design methods, using orthogonal experimental design to design the C/Cu composites wear test. Finally determine the C/Cu composites wear test plan, including a group of orthogonal test and three simple comparison verification tests.(3) Friction and wear testing machine design. Design C/Cu composites specimen clamping device using the knowledge of the compliant mechanism, which is used as loading part of C/Cu composites wear testing machine. The C/Cu composites specimen clamping device is analyzed by the pseudo-rigid-body model method, including the relationship between force and displacement, dynamic characteristics and frequency characteristic, then analyse the model with finite element analysis method. Design the friction and wear testing machine based on the C/Cu composites specimen clamping device. The autonomously designed testing machine has three modes:reciprocating sliding, ring-block sliding and pin-disc sliding and it is convenient to realize different mode conversion.(4) Wear test results and data analysis. Run C/Cu composites wear test under the reciprocating sliding mode for about1520hours. Analysis the data and draw the conclusion that carbon contenthas the greatest impact on C/Cu composites’ wear rate, followed by load and speed, and wear rate decreases with the increase of carbon content and speed, while increases with load increasing. The results verify the theoretical analysis before. The three simple comparison verification tests show that water increases wear and acidic liquid leads to severe wear. Finally observe the surface morphology of C/Cu composites specimen and analysis the wear mechanism under different test conditions.