【摘要】 目的采用超声纵-扭复合振动加工方法,获得较长的刀具使用寿命。方法采用理论建模与不同铣削振动方式,研究刀具磨损特性。通过超景深电子显微镜和粗糙度测试仪,分别对刀具微观形貌、工件表面粗糙度进行了分析;通过不同铣削方式加工钛合金材料,对刀具磨损特性进行了系统分析。结果与普通铣削和超声纵振铣削相比,超声纵-扭铣削方式下,刀具后刀面磨损减小,工件表面粗糙度降低。经测试,当去除面积为6356mm~2时,超声纵-扭复合加工刀具后刀面磨损量VB为103μm,分别比普通和超声纵振加工时降低了38μm和36μm。当去除面积为4530 mm~2时,Ra为1.2μm,普通铣削和超声纵振铣削的Ra则分别为1.62μm和1.38μm。由于超声纵振加工仅仅是在轴向方向实现了分离,后刀面时刻冲击着已加工表面,当去除面积为6356 mm~2时,刀具后刀面磨损量反有超出普通铣削的趋势。结论超声纵-扭复合加工从旋转方向内实现了刀-屑分离,在铣削过程中,极大地减少了刀具后刀面对已加工表面的冲击,从而使得刀具寿命有所延长,为高效加工、难加工材料提供了一种加工方法。更多还原

【Abstract】 The work aims to obtain longer tool life in ultrasonic longitudinal-torsional vibration milling. The tool wear characteristics were studied by theoretical modeling and different milling vibration modes. The surface topography of the tool and surface roughness of the workpiece were analyzed by the electron microscope(VHX-2000) and surface profiler. Titanium alloys materials were processed by different milling methods and the wear characteristics of tool were analyzed systematically.Compared with the ordinary and ultrasonic longitudinal vibration milling, the ultrasonic longitudinal-torsional vibration milling reduced the wear on the flank surface of tool and improved the roughness of workpiece surface. Through the test, when the removal area was 6356 mm~2, the flank wear under the ultrasonic longitudinal-torsional vibration milling was 103 μm, respectively dropping by 38 μm and 36 μm than that under ordinary and longitudinal ultrasonic milling. When removal area was 4530 mm~2,the roughness Ra was 1.2 μm and Ra for the ordinary and the longitudinal vibration were 1.62 μm and 1.38 μm respectively.Due to the axial separation of ultrasonic longitudinal vibration, the flank continuously impacted the processed surface. The ultrasonic longitudinal vibration method caused more flank wear than the ordinary when removal area reached 6256 mm~2. Ultrasonic longitudinal-torsional vibration machining realizes the actual separation of tool and chip in rotation direction and greatly reduces the impact to the processed surface by flank, thus extending the tool life and providing a new machining method for high-efficient processing and difficult-to-machine-material.更多还原