不同冷却润滑方式对切削SiCP/Al复合材料刀具磨损的影响

为探究不同冷却润滑方式对切削SiC_P/Al复合材料刀具磨损的影响，进行了干切削（Dry）、微量润滑（MQL）、液氮（LN₂）、切削油（Oil）和乳化液（Emulsion）共五种冷却润滑条件下的车削实验，分析了冷却润滑方式对刀具边界磨损、刀具破损和后刀面磨损的影响。结果表明:MQL和LN₂有更佳的流体冲刷效果，可以将脱落的SiC颗粒及时带离切削区，减少边界磨损； Oil和Emulsion冲刷效果较差，会加剧边界磨损。LN₂的使用会增加刀具受到的热应力和机械冲击，积屑瘤发生完全脱落，造成切削过程不平稳，当切削距离达到1 100 m时，刀具发生破损； Oil切削时，严重的边界磨损导致刀尖部位尺寸减小，强度降低，当切削距离达到825 m时发生了刀具破损。MQL良好的润滑渗透性和LN₂有效的冷却效果可以减少后刀面磨损。因此，MQL兼具冷却、润滑和流体冲刷效果，更加适合作为切削SiC_P/Al复合材料的冷却润滑方式。 

Influence of different cooling and lubrication methodson tool wear in machining SiCP/Al composites

In order to study the influence of different cooling and lubrication methods on tool wear in machining SiC_P/Al composites, the turning experiments with cooling and lubrication methods including dry, liquid nitrogen (LN₂), minimum quantity lubrication (MQL), cutting oil (Oil) and emulsion were carried out, the influences of cooling and lubrication methods on tool boundary wear, tool breakage and flank wear were analyzed. The results show that MQL and LN₂ can bring the detached SiC particles away from the cutting zone due to their more effective flushing characteristic, which contributes to the decrease of boundary wear; the application of Oil and Emulsion deteriorates boundary wear intensely because of less flushing ability. The increase in the thermal stress and mechanical shocking applied to the tool and build-up edge shedding will cause the cutting process to be unstable with the application of LN₂, resulting in tool breakage at the cutting distance of 1 100 m; when turning with Oil, serious boundary wear can decrease the tool nose size and lead to reducing of intensity of the tool nose, so tool breakage occurs at the cutting distance of 825 m. Flank wear decreases due to MQL's great lubrication permeability and LN₂' effective cooling effect. Therefore, MQL possesses good cooling, lubrication and fluid flushing effects and is a better cooling and lubrication method for machining SiC_P/Al composites.