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对传统等通道转角挤压工艺(equal channel angular extrusion,ECAE)进行改进,提出一种新型剧烈塑性变形法(severe plastic deformation,SPD)——等通道球形转角膨胀挤压(equal channel angular expansion extrusion with spherical cavity,ECAEE-SC).该工艺通过耦合镦-剪-挤等多种变形效应,可在单道次挤压下实现坯料内部较大的塑性应变累积,进而获得理想的晶粒细化与性能提升效果.在室温条件下采用ECAEE-SC 工艺对工业纯铝(Al-1060)进行单道次挤压,并与相同条件下的2 道次ECAE 处理变形结果进行对比.采用EBSD、SEM 等测试手段,研究了工业纯铝经ECAEE-SC 变形晶粒特征与磨损表面形貌,并测试了变形材料显微硬度、拉伸性能与摩擦学性能.结果表明,在ECAEE-SC 工艺剧烈塑性应变诱导下,工业纯铝经单道次挤压变形后晶粒显著细化,呈典型的剪切条带状特征.与初始退火态相比,变形材料显微硬度与抗拉伸强度分别提升了92.6％和91.8％,且性能提升效果明显优于2 道次ECAE 变形.同时,ECAEE-SC 工艺有效提高了工业纯铝的耐磨性能,工业纯铝变形后表面磨痕宽度最小,磨痕深度最浅,其磨损机理以磨粒磨损为主导.“,”A novel severe plastic deformation(SPD)method,namely equal channel angular expansion extrusion with spherical cavity(ECAEE-SC),was introduced based on the modification of conventional equal channel angular extrusion(ECAE)process.By integrating expansion,shear and extrusion deformations in a single extrusion pass,ECAEE-SC process can induce larger accumulated strains into the billet,resulting in the significant grain refinement and improvement of the associated properties.In the present study,commercially pure aluminum(Al-1060)was subjected to one pass of ECAEE-SC process at room temperature,and two passes of ECAE process for comparison.The microstructure,Vickers hardness,tensile properties and wear properties of processed material were investigated.The results show that after one pass of ECAEE-SC process,the grains of ECAEE-SC processed aluminum are greatly refined with a typically elongated microstructure due to the high level strains induced in the material.The hardness and tensile strength of ECAEE-SC processed material increase significantly by almost 92.6％and 91.8％than those of the initial material,respectively.These improvements are considerately higher than those achieved by two passes of ECAE process.Moreover,the wear resistance of ECAEE-SC processed material is also enhanced.The worn surface morphology of ECAEE-SC processed sample presents the minimum width and depth of the wear scars,indicating that the wear mechanism is dominated by abrasive wear.