Microstructure and Properties of Micro-Alloyed Mg-2.0Nd-0.2Sr by Heat Treatment and Extrusion  

作　　者：Zhenzhen Gui Fan Jiang Zhixin Kang Fan Zhang Zu Li Jianhui Zhang 

机构地区：[1]School of Mechanical and Electrical Engineering,Guangzhou University,Guangzhou,510006,China [2]Joint Institute of Guangzhou University and Institute of Corrosion Science and Technology,Guangzhou University,Guangzhou,510006,China [3]Guangdong Key Laboratory for Advanced Metallic Materials Processing,School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou,510640,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2023年第2期323-334,共12页金属学报（英文版）

基　　金：supported by the Fast Support Project(No.80923010304);the Guangdong Basic and Applied Basic Research(Nos.2022A1515010265 and 2020A1515110619);the Guangzhou Science and Technology Plan Project(No.202002030356);the R&D Program of Joint Institute of GZHU&ICoST(Nos.GI202108 and GI202110).

摘　　要：Magnesium(Mg)and its alloys have broad application prospects in the fields such as biomedical materials and automobile manufacturing.A micro-alloyed Mg-2.0Nd-0.2Sr(wt.%)magnesium alloy is designed and obtained through semicontinuous casting.The evolution of microstructures and tensile properties are investigated with different heat treatments and extrusion treatments.The grain sizes decrease significantly after extrusion,thus changing the fracture mode during the tensile testing process.The ultimate tensile strength(UTS),yield strength(YS)and elongation(EL)of the properly processed extrusion alloy(referred to as MNS-E2)reach to 247 MPa,228 MPa and 24%,respectively.The dramatical improvement of mechanical properties results from the refined grains and interactions between dislocations and precipitates.Some nanoparticle bands blocking the slippage and movement of dislocations are also found in the MNS-E2 alloy.The above causes combined result in an integrated effect of grain boundary strengthening,dislocation strengthening,precipitation strengthening and nanoparticle band strengthening.The contribution of strengthening mechanisms of MNS-E2 alloy consists of grain boundary with around 96 MPa,dislocations with around 3.4 MPa,precipitation strengthening with around 45 MPa and the nanoparticle band with around 18 MPa,respectively.

关 键 词：Mg-Nd-Sr alloy Hot extrusion Mechanical properties Strengthening mechanisms 

分 类 号：TG146[一般工业技术—材料科学与工程]