中文摘要：

在自行研制的新型旋转挤出加工装置的基础上，设计了凹槽型和螺纹型芯棒，对比研究了芯棒几何结构对聚乙烯（PE）管结构与性能的影响。实验结果表明，凹槽型芯棒不利于串晶的形成，而螺纹型芯棒对串晶的产生有明显促进效果。因而，在旋转挤出和螺纹型芯棒耦合作用下，可形成大量偏离轴向排列的串晶结构，从而提高PE管的环向强度。相较于常规挤出PE管，制备的PE管环向强度为29．3 MPa，提高幅度达34％。

英文摘要：

In this study, the groove-type and screw-type mandrels were designed, and the geometricstructure effects on the structure and properties of polyethylene （PE） pipes prepared via self-designedrotation extrusion equipment were studied. The experimental results show that the groove-type mandrel is notconducive to the formation of shish-kebab while the screw-type mandrel has the promoting effect. As a result,under the coupling effect of rotation extrusion and the screw-type mandrel, a large number of shish-kebabcrystals off the axial direction are generated in the PE pipe to improve the hoop strength greatly to 29. 3 MPawhich is increased by 34% compared to the convention-extruded PE pipe.