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Study on friction properties of different abrasive materials and polylactic acid materials

In recent years, 3D printing technology is often used in various fields such as industry, medical care, and academia, because it can produce components with complex shapes at a lower cost than traditional processing. However, the size of 3D products is often limited by the printable range of printing equipment, so large objects often need to be disassembled and printed before joining. Friction stir welding is used to join different thermoplastics and has considerable potential for industrial applications, and the influence of the design of the welding tool on the formation of the welding zone is an important key. In this study, different abrasive materials and polylactic acid materials were used for friction, and the changes of friction coefficient and friction temperature during the friction process were discussed. The experimental results show the surface roughness of the abrasive tool has a significant effect on the coefficient of friction and temperature rise. As increasing the roughness of the abrasive tool, the wear scars, the cracks below the wear scar are both significant. It can be inferred from the crack shape that the PLA softens at high temperatures and then solidifies again, so the cracks are seen with a streamlined appearance, which means that the softened PLA can be carried by the abrasives tool with highly rough surfaces.