硬质合金刀具的动态可靠性灵敏度研究

刀具各设计参数的选取直接影响刀具的可靠度和被加工件的精度。以应力-强度干涉（SSI）模型为基础，建立硬质合金刀具的动态可靠性数学模型，给出了刀具在切削加工时的可靠度变化规律。在此基础上与灵敏度分析方法相结合，推导出硬质合金刀具物理参数和材料参数的动态可靠性灵敏度计算公式，并给出了各参数的动态可靠性灵敏度的变化曲线。研究结果表明，随着切削加工时间和冲击载荷作用次数的增加，刀具各参数的敏感程度也逐步增大，对敏感参数可以通过直接或间接的手段加以控制，以降低对刀具可靠度的影响，进而提高刀具的可靠度和被加工零件的精度。该方法为提高刀具系统及整个机床的可靠性提供理论参考依据。

Research on Dynamic Reliability Sensitivity of Hard Alloy Cutting Tool

The selection of design parameters of cutting tool has the direct effect on the reliability of tools and the precision of processed workpiece. Based on stress-strength interference model, a mathematical model on dynamic reliability of hard alloy cutting tool is built, and the change rule of its reliability is obtained. Combining with sensitivity analysis method, the computational formulas of dynamic reliability sensitivity of physical and material parameters of hard alloy cutting tool are deduced, and the curves of reliability sensitivity of design parameters are also given. The results show that the design parameters of cutting tool are more sensitive with the increase in machining time and impact loading action, thus the selection of sensitive parameters should be controlled directly or indirectly so as to reduce its influence on reliability of cutting tool, which can improve the reliability of cutting tool and the precision of processed workpiece. Meanwhile, the proposed method provides a theoretical basis for enhancing the reliability of tool system and the whole machine tool.