Research On Residual Stress And Optimization Of Cutting Parameters In Aluminum Alloy Piston Skirt Machining

As a key component to transfer movement and power of the diesel engines, the machining quality and process reliability of the piston directly affect the service performance of the diesel engines. In this dissertation, the cutting force, cutting temperature and residual stress in the piston skirt machining are studied. The particle swarm algorithm is used to implement the optimization of cutting parameters. The main contents are as follows:1. Based on the Johnson-Cook flow stress model and Oxley cutting model, the theoretical prediction model of cutting force is established for the ZL109 aluminum alloy piston skirt machining. The effects of cutting parameters and tool parameters on cutting force are studied.The cutting temperature prediction model is established using mirror heat source method, and the temperature distribution at different cutting speeds is analyzed.2. The distribution of stress is analyzed based on the metal cutting and elastic-plastic theory. The theoretical prediction model of residual stress of ZL109 aluminum alloy piston skirt machining is established, and then the influences of cutting parameters and tool parameters on residual stress of piston skirt machining are studied.3. According to the elastic-plastic theory, the three-dimensional finite element model of ZL109 aluminum alloy piston skirt machining is established using the DEFORM software. The cutting force, cutting temperature and machining residual stress during piston skirt cutting are simulated by the finite element method. The effects of cutting parameters and tool parameters on cutting force, cutting temperature and residual stress are analyzed.4. On the basis of the characteristics of piston skirt machining, the constraints in this optimization problem are defined with the combination of the processing system performance parameters and residual stress requirements. The particle swarm algorithm is used to optimize the cutting parameters to achieve high efficiency.The research in this dissertation can provide reference and theoretical basis to the piston cutting and the optimization of cutting parameters.