Study On Theroy And Experiment Of Wire Drawing With Ultrasonic For Practical Application

As a kind of ultrasonic plastic processing technology,wire drawing with ultrasonic is a new processing technology through transferring ultrasonic vibratio -n to common wire drawing.It has been paid extensively attention to from home to abroad for its outstanding features such as reducing drawing force,improving surface quality and increasing processing efficiency,various machinable material, etc.There is no satisfying explain for the theory of ultrasonic wire drawing.The ultrasonic wire drawing has been stagnated in the groping phase and can't be applied to practice for a long time.Base on other pursuer's research,this thesis introduces the factor affecting metallic plastic transmutation and the basic of metallic wire drawing.Based on reading and analyzing a large quantity of correlative references,the theory of ultrasonic drawing was studied and experiments were done.The main factor affecting metallic plastic transmutation in different phase were analysed;and the function of ultrasonic vibration were explained.The drawing-force were calculated in wire-drawing with and withnot ultrasonic vibration.Base on the one-dimensional and longitudinal vibration locomotory equation of variable cross-sectional bar,some fundamental formulas used analytically are given,and vibration apparatus with a half-wavelength longitudinal transducer is designed by the principle and requirements of wire-drawing system with ultrasonic vibrations,the vibration modes and characteristics were analyzed by the aid of FEM for its correct design.Also,for the sake of ensuring wire-drawing experiment's efficiency,vibration measurement of the vibration apparatus is realized by microscope on the base of match analysis of the ultrasonic drive supply and the vibration apparatus,according to whose circuit model impedance is measured by a impedance analyzer.Finally,wire-drawing experiment on a practical drawbench were carried out. Because of idler pulley adjust tensile force,the drawing-force appear exceptional peak,more quicker and more impurity it is more obvious;the drawing-force value, surface topography and microstructure topography affected by vibration intensity and drawing velocity are worth to be also attentive.By qualitative analysis of the experiment,the effects of ultrasonic to drawing force owns to changing of friction vector's direction,reduction of friction factor and the die's high-speed impact to wire,ultrasonic vibration can reduce drawing force and improve the quality of the copper-wire when the input voltage is up to some value while ultrasonic vibration transfers to the die.