| With the rapid development of global industrial technology, the application of highperformance materials such as titanium alloy is increasing. These materials haveexcellent mechanical properties and corrosion resistance, but its cutting performance isdisappointing. Conventional machining processing quality can’t meet the requirements,but cannot guarantee lower processing costs. In order to meet the urgent needs ofhigh-precision cutting difficult-to-machine materials, based on the ultrasonic vibrationcutting technology, numerical simulation and experimental research on ultrasonicvibration assistance turning in feed direction were carried out.Ultrasonic vibration assistance turning in feed direction is to make the cutter forharmonic vibration along the feed direction of workpiece using vibration device basedon the conventional turning, which changes the original motion state between cutter andworkpiece. By knowing one dimensional ultrasonic vibration turning research status athome and abroad, found that most scholars study the vibration of the cutting process arebased on the cutter for harmonic vibration in the direction of the cutting speed. Theprocess of the cutter for high frequency impacting the workpiece, the reciprocatingfriction between workpiece and rake face in the third deformation zone are easy to causethe collapse edge, which adversely affect the result of the processing. In order to avoidthis phenomenon, the research on the ultrasonic vibration assistance in feed directionturning is carried out, based on ultrasonic vibration cutting theory, by the method ofnumerical simulation and experiments. The main contents are as follows:Firstly, ultrasonic vibration assistance in feed direction turning motion relationshipbetween cutter and workpiece is analyzed, discussing the influence of different cuttingparameters, vibration parameters on the cutting force, chip formation. It is concludedthat the ultrasonic vibration assistance in feed direction turning can achieve intermittentcutting, when the double amplitude value greater than or equal to feed speed (2a S)and the phase difference S2a, by the above analysis. In addition, throughanalyzing the characteristics of ultrasonic vibration assistance in feed direction turningcutter motion in the direction of feed and cutting speed direction, the surface topographyof3D model is established.Secondly, using the finite element software of Abaqus, the traditional cutting and ultrasonic vibration assistance in feed direction turning two-dimensional simulationmodel is established based on the key technology of numerical simulation. Realized theintermittent cutting in the numerical simulation of ultrasonic vibration assistance in feeddirection turning, this phenomenon is consistent with the theoretical analysis results. Inaddition，the prediction of cutting area of stress distribution, strain distribution, thecutting force, and cutting temperature trend along with the change of cutting parametersis carried out under two different cutting methods through two-dimensional cuttingnumerical simulation method.Finally, conventional turning and ultrasonic vibration assistance in feed directionturning comparative experiment was carried out. By means of the simulation andexperimental results of the two kinds of turning of the main cutting force, the axialcutting force signal, the analysis found that intermittent cutting phenomenon inultrasonic vibration assistance in feed direction turning, and enough to reduce the maincutting force. Roughness is reduced in ultrasonic vibration assistance in feed directionturning by comparing the results of conventional turning surface roughness, and similarto the3d model of surface microstructure was observed.The paper relies on the cutting mechanism analysis, numerical simulation andcomparison experiment, confirmed ultrasonic vibration assistance in feed turningtitanium alloy can reduce the cutting force, improve the quality of surface. |
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