The in-situ TiB₂ particle reinforced aluminum matrix composites are materials that are difficult to machine, owing to hard ceramic particles in the matrix. In the milling process, the polycrystalline diamond (PCD) tools are used for machining these materials instead of carbide cutting tools, which significantly increase the machining cost. In this study, ultrasonic vibration method was applied for milling in-situ TiB₂/7050Al metal matrix composites using a TiAlN coated carbide end milling tool. To completely understand the tool wear mechanism in ultrasonic-vibration assisted milling (UAM), the relative motion of the cutting tool and interaction of workpiece-tool-chip contact interface was analyzed in detail. Additionally, a comparative experimental study with and without ultrasonic vibration was carried out to investigate the influences of ultrasonic vibration and cutting parameters on the cutting force, tool life and tool wear mechanism. The results show that the motion of the cutting tool relative to the chip changes periodically in the helical direction and the separation of tool and chip occurs in the transverse direction in one vibration period, in ultrasonic vibration assisted cutting. Large instantaneous acceleration can be obtained in axial ultrasonic vibration milling. The cutting force in axial direction is significantly reduced by 42%–57%, 40%–57% and 44%–54%, at different cutting speeds, feed rates and cutting depths, respectively, compared with that in conventional milling. Additionally, the tool life is prolonged approximately 2–5 times when the ultrasonic vibration method is applied. The tool wear pattern micro-cracks are only found in UAM. These might be of great importance for future research in order to understand the cutting mechanisms in UAM of in-situ TiB₂/7050Al metal matrix composites.

中文翻译：

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轴向超声振动辅助铣削TiB 2 / 7050Al金属基复合材料的刀具磨损机理

原位TiB ₂颗粒增强的铝基复合材料是由于基体中坚硬的陶瓷颗粒而难以加工的材料。在铣削过程中，使用多晶金刚石（PCD）工具代替硬质合金切削刀具来加工这些材料，这大大增加了加工成本。在这项研究中，超声振动方法被用于原位研磨TiB ₂/ 7050Al金属基复合材料，使用TiAlN涂层硬质合金立铣刀。为了全面了解超声振动辅助铣削（UAM）中的刀具磨损机理，详细分析了刀具的相对运动以及工件-刀具-切屑接触界面的相互作用。另外，进行了有或没有超声振动的对比实验研究，以研究超声振动和切削参数对切削力，刀具寿命和刀具磨损机理的影响。结果表明，在超声振动辅助切削中，切削刀具相对于切屑的运动在螺旋方向上周期性变化，并且在一个振动周期内，刀具和切屑的分离在横向方向上发生。在轴向超声振动铣削中可以获得较大的瞬时加速度。与传统铣削相比，在不同的切削速度，进给速度和切削深度下，轴向切削力分别显着降低了42％–57％，40％–57％和44％–54％。此外，采用超声振动法时，刀具寿命可延长约2至5倍。仅在UAM中发现工具磨损型微裂纹。这些对于以后的研究可能非常重要，以了解原位TiB UAM中的切割机制。采用超声振动法时，刀具寿命可延长约2–5倍。仅在UAM中发现工具磨损型微裂纹。这些对于以后的研究可能非常重要，以了解原位TiB UAM中的切割机制。采用超声振动法时，刀具寿命可延长约2–5倍。仅在UAM中发现工具磨损型微裂纹。这些对于将来的研究可能非常重要，以便了解原位TiB UAM中的切割机制₂ / 7050Al金属基复合材料。