脉振模压成型对UHMWPE中空制件结构与性能的影响

Influence of Pulse Vibration Molding on the Structure and Performance of UHMWPE Hollow Parts

为了提高超高分子量聚乙烯(UHMWPE)中空制件的机械性能和耐磨性能,采用自主研制的中空制件成型模具,在模压成型过程中引入脉冲振动,使物料在脉冲压力下实现成型,并通过拉伸测试、砂浆磨耗测试、热分析测试、密度测试和2D-WAXD(二维广角X衍射仪)测试,研究脉冲振动对制件微观结构及宏观性能的影响,同时与静态成型条件下的中空制件对比。结果表明:在致密化阶段施加脉冲振动可有效提高制品的致密化程度;在冷却结晶阶段施加脉冲振动时,制品的取向度与结晶度均得到提高。脉振条件下成型制件的拉伸性能和耐磨性能均优于静态条件下成型的制件。

In order to improve the mechanical properties and wear resistance of ultra-high molecular weight polyethylene(UHMWPE)hollow parts,an experiment was carried out on a self-developed hollow part forming mold.Pulse vibration was introduced into the compression molding process,so that the material can be formed under pulse pressure.The influence of impulsive vibration on the microstructure and macroscopic properties of the parts was studied through tensile test,mortar abrasion test,DSC test,density test and 2D-WAXD test.The results show that pulse vibration introduced in the densification stage can effectively improve the densification degree of the sample;pulse vibration introduced in the cooling crystallization stage can improve the orientation and crystallinity of the sample.The tensile properties and wear resistance of the sample molded under the pulse vibration condition are be-tter than those molded under the static condition.