管材液压成形中表面粗糙度与液体压强对摩擦系数的影响  

Effects of surface roughness and hydraulic pressure on friction coefficient in tube hydroforming

作　　者：吴春蕾[1] 杨连发[1] 

机构地区：[1]桂林电子科技大学机电工程学院,广西桂林541004

出　　处：《锻压技术》2014年第11期74-80,共7页Forging & Stamping Technology

基　　金：国家自然科学基金资助项目(51271062);广西自然科学基金资助项目(2013GXNSFAA019305);桂林电子科技大学研究生教育创新计划资助项目(GDYCSZ201401)

摘　　要：通过对管材液压成形过程进行有限元仿真,构建管材内液体产生的压力与管材和模具之间接触压力的关系。为了揭示液体压强和表面粗糙度对摩擦系数的影响规律,提出一种管材和模具之间摩擦系数的有限元确定方法。采用商业有限元软件ABAQUS,基于表面粗糙度定义建立了管材液压成形二维有限元模型,模型包括管材和模具之间接触表面完全光滑和不同粗糙度的情况,其中粗糙表面轮廓采用正弦曲线表达。研究结果表明:接触压力与液体产生的压力偏差率值较小;液体压强越大,管材与模具之间的摩擦系数越小,而且摩擦系数变化曲线的导数越趋近于0;管材表面粗糙度越大,摩擦系数越大,但是摩擦系数的偏差并不明显。The relationship between the force generated by liquid and the contact force between tube and die was built by finite element simulation of the tube hydroforming.In order to reveal the effect law of surface roughness and hydraulic pressure on friction coefficient,a method about the determining of the coefficient of friction（COF） between tube and die was proposed based on the finite element.According to the definition of surface roughness,the FE model of tube hydroforming was conducted including various contacting conditions between tube and die from perfect smooth to different roughness by the commercial software ABAQUS,in which the surface morphology was expressed using the sinusoidal-profile surfaces.The results show that the deviation rate between the force generated by liquid and the contact force is small.The more the hydraulic pressure,the less the COF between tube and die,and the derivative of COF curve approaches zero.The more the surface roughness of tube,the more COF,but the deviation of COF is not obvious.

关 键 词：管材液压成形 表面粗糙度 液体压强 摩擦系数 

分 类 号：TG394[金属学及工艺—金属压力加工]