Study on grinding process and surface defects of SiCp/Al with 20 % volume fraction.

This experiment was designed to study the surface defects of 20 % volume fraction SiCp/Al composites after grinding and to provide the necessary experimental results for optimizing grinding parameters. Based on the two-dimensional cutting simulation model of single particle, the main damage of particles in matrix during machining has been investigated. The particles in SiCp/Al composites are randomly distributed and the tool will cut through multiple particles in a single cut and at different locations. A single particle cutting model was developed to study the different states of particle fragmentation by cutting through the upper, middle and lower parts of the particles respectively. Nine groups of parameters were obtained by orthogonal experimental design, and electroplated diamond grinding rod was used as the grinding tool for grinding experiment. In order to get the best surface grinding parameters, a ternary linear regression equation was selected to be established. Significance test could prove the reliability of the linear regression equation, and then, the optimal solution of this equation can be calculated by the MATLAB genetic algorithm toolbox. From the simulation and experimental results, it can be seen that the stress begins to concentrate when the cutting tool is close to the particle, and when the cutting stress exceeds the ultimate compressive strength, the particle is broken and part of it will be pulled out. The breakage of particles is not one-time, but requires many times of large cutting force to break the particles in sections, and the repeated breakage of particles eventually leads to the generation of overall cracks. [ABSTRACT FROM AUTHOR]