To enhance the mechanical properties and corrosion resistance of magnesium alloys,high-energy shot peening(HESP)was used.According to the results,the in-situ surface nanocrystallization(ISNC)microstructure was fabrica...To enhance the mechanical properties and corrosion resistance of magnesium alloys,high-energy shot peening(HESP)was used.According to the results,the in-situ surface nanocrystallization(ISNC)microstructure was fabricated on the magnesium alloy surface,and its formation mechanism was the coordination among twins,dislocations,subgrain boundary formation and dynamic recrystallization.Under the released surface stress of sample,the residual compressive stress and microhardness rose,thus enhancing compactness of the surface passivation film Mg(OH)2.Besides,the corrosion rate dropped by 29.2% in maximum.In the polarization curve,the maximum positive shift of the corrosion potential of sample was 203 mV, and the corrosion current density decreased by 31.25% in maximum.Moreover,the compression resistance and bending resistance of the bone plate were enhanced,and the maximum improvement rates were 18.2% and 23.1%,respectively.Accordingly,HESP significantly enhanced mechanical properties and corrosion resistance of magnesium alloys.展开更多
文摘[目的]总结儿童肱骨远端全骺分离的解剖基础、损伤特点及诊断要点,探讨手术治疗的方法、意义及相关问题的处理。[方法]1998~2006年,收治12例肱骨远端全骺分离患儿,按Delee分型:A型2例,B型4例,C型6例,受伤至手术时间12 h之内4例,24 h之内3例,24~72 h 5例,均行切开复位克氏针内固定,术后拍片复查,3~6周拔除克氏针行功能锻炼。[结果]本组12例,随访6个月~8年,平均37个月,骨折愈合时间3~6周,平均4.6周;患肘屈伸活动良好,无1例发生肘内翻。[结论]手术切开复位内固定治疗儿童肱骨远端全骺分离,可以解剖复位,预防肘内翻,最大程度地恢复患肢功能。
基金Project(51872122) supported by the National Natural Science Foundation of ChinaProjects(2017GGX30140,2016JMRH0218) supported by the Key Research and Development Plan of Shandong Province,ChinaProject(2016-2020) supported by Taishan Scholar Engineering Special Funding of Shandong Province,China
文摘To enhance the mechanical properties and corrosion resistance of magnesium alloys,high-energy shot peening(HESP)was used.According to the results,the in-situ surface nanocrystallization(ISNC)microstructure was fabricated on the magnesium alloy surface,and its formation mechanism was the coordination among twins,dislocations,subgrain boundary formation and dynamic recrystallization.Under the released surface stress of sample,the residual compressive stress and microhardness rose,thus enhancing compactness of the surface passivation film Mg(OH)2.Besides,the corrosion rate dropped by 29.2% in maximum.In the polarization curve,the maximum positive shift of the corrosion potential of sample was 203 mV, and the corrosion current density decreased by 31.25% in maximum.Moreover,the compression resistance and bending resistance of the bone plate were enhanced,and the maximum improvement rates were 18.2% and 23.1%,respectively.Accordingly,HESP significantly enhanced mechanical properties and corrosion resistance of magnesium alloys.