By using a novel surface modification technique named ultrasonic-electropulsing coupling rolling (UECR) process on an Al-Si casting alloy rod, the surface of material was smoothened significantly. Meanwhile, a stren...By using a novel surface modification technique named ultrasonic-electropulsing coupling rolling (UECR) process on an Al-Si casting alloy rod, the surface of material was smoothened significantly. Meanwhile, a strengthened layer with agradient change in hardness was obtained in the outer surface, corresponding to a homogeneous gradient nano-/micro-structure. The thickness of nanometer-thick laminated structures was at least 40 μm, which was much thicker thanconventional ultrasonic rolling process. During UECR, the formation of the well-defined nanocrystalline structure wasattributed to the high strain rate and simultaneous annealing process realized by ultrasonic impact and electropulsingtreatment.展开更多
基金financially supported by the Shenzhen Nanshan District Governmental Foundation(Grant No.KC2015ZDYF0021A)the Shenzhen Industry Development Foundation(Grant No.HYCYGJ20140512010015)the Shenzhen Development and Reform Commission Foundation(Grant No.2015-1033)
文摘By using a novel surface modification technique named ultrasonic-electropulsing coupling rolling (UECR) process on an Al-Si casting alloy rod, the surface of material was smoothened significantly. Meanwhile, a strengthened layer with agradient change in hardness was obtained in the outer surface, corresponding to a homogeneous gradient nano-/micro-structure. The thickness of nanometer-thick laminated structures was at least 40 μm, which was much thicker thanconventional ultrasonic rolling process. During UECR, the formation of the well-defined nanocrystalline structure wasattributed to the high strain rate and simultaneous annealing process realized by ultrasonic impact and electropulsingtreatment.