Surface Roughness and Microstructure in Ultrasonically Assisted Turning of W-Fe-Ni Alloy

The experiment is carried out of turning W-Fe-Ni alloy by conventional turning and ultrasonically assisted turning. Effects of cutting parameters and vibration parameters on surface roughness are studied. The significant factors influence surface roughness by the orders of feed rate, tool amplitude and tool frequency in ultrasonically assisted turning, whereas the main factors influence surface roughness is feed rate in conventional turning. Using ultrasonically assisted turning can reduce surface roughness by 7.05%30.06% compared with conventional turning in same cutting parameters in experiments. To analyze the characteristics of surface machined, X ray diffractometer, white light interferometer and scanning electronic microscope are used to observe micro surface profile. It is confirmed that apart from the regular feed marks with an equal spacing, there are also regular parallel stripes on the finished surface in ultrasonically assisted turning. It is intense ironing effects that reduce the surface roughness and increase compressive stress. A high quality surface can be obtained by selecting appropriate parameters in ultrasonically assisted turning.