Tailoring the austenite characteristics via dual nanoparticles to synergistically optimize the strength-ductility in cold rolled medium Mn steel  

作　　者：Qizhe Ye Haokai Dong Qinyi Guo Yishuang Yu Lijie Qiao Yu Yan 

机构地区：[1]Beijing Advanced Innovation Center for Materials Genome Engineering,Corrosion and Protection Center,Institute for Advanced Materials and Technology,University of Science and Technology Beijing,Beijing 100083,China [2]School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou 510641,China [3]School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China [4]School of Biomedical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China

出　　处：《Journal of Materials Science & Technology》2024年第2期158-171,共14页材料科学技术（英文版）

基　　金：support received from the National Natural Science Foundation of China(Grant No.U1964204).

摘　　要：In this work,we proposed a novel Cu/θdual nanoparticles strategy to tailor the austenite characteris-tics of a medium Mn steel via a tempering-annealing process to optimize the mechanical properties.We explored the effects of Cu-rich particles and cementite precipitated in the tempering process on the austenite reversion during the subsequent annealing process.Both experiments and numerical simula-tions verified that the austenite inherited from cementite had a finer size and a higher Mn enrichment compared with the austenite originating from the tempered martensite matrix.In addition,quantitative evaluations revealed that the pinning effect exerted by the Cu-rich particles could significantly hinder theα/γinterface migration and the recrystallized grain growth,thereby further refining the final mi-crostructure.With contributions from the effects of dual nanoprecipitates on the austenite reversion,the heterogeneous austenite grains inherited from varying nucleation sites ensured the sustained and gradual deformation-induced martensite and twinning formation.Therefore,the Cu-added steels subjected to a tempering-annealing process achieved synergetic enhancement of the tensile strength from 1055 MPa to 1250 MPa and elongation from 33%to 45%.This strategy may provide new guidance for the development and alloy design of high-performance medium Mn steels.

关 键 词：Dual nanoparticles Medium Mn steel Tempering-annealing process Austenite reversion Mechanical properties 

分 类 号：TG142.1[一般工业技术—材料科学与工程]