【摘要】 沙漏挤压是一种新的晶粒细化方法 ,通过挤压过程中产生的大塑性变形和动态再结晶而使晶粒得到细化。本文采用 Zn- Al合金对这种工艺进行了初步研究 ,重点研究了变形量对沙漏挤压效果的影响。给出了显微组织变化和力学性能与超塑性能变化的初步结果。实验结果表明 :采用沙漏挤压能使材料获得等轴超细晶组织 ,材料性能得到很大的提高 ,并有助于实现高应变速率超塑性更多还原

【Abstract】 A new method of getting ultrafine grain has been investigated,which is called“Sandglass Extrusion”(SE).The ultrafine grain can be obtained in the billet material due to the large plastic strain and the dynamic recrystallization during SE.The microstructures,microhardness and superplasticity of test material after SE have been studied.The experimental results show that the equal axial ultrafine microstructures can be introduced to the bulk test material during sandglass extrusion.The high strain rate superplasticity can be realized.更多还原