含Cu的HSLA钢中富Cu团簇的粗化行为及其对力学性能的影响  

Coarsening behavior of Cu-rich clusters in a Cu bearing HSLA steel and its effect on mechanical properties

作　　者：杜瑜宾 胡小锋[1] 宋元元[1] 姜海昌[1] 戎利建[1] DU Yu-bin;HU Xiao-feng;SONG Yuan-yuan;JIANG Hai-chang;RONG Li-jian(CAS Key Laboratory of Nuclear Materials and Safety Assessment,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China)

机构地区：[1]中国科学院金属研究所中国科学院核用材料与安全评价重点实验室,辽宁沈阳110016 [2]中国科学技术大学材料科学与工程学院,辽宁沈阳110016

出　　处：《材料热处理学报》2021年第9期136-143,共8页Transactions of Materials and Heat Treatment

基　　金：国家重点研发计划(2016YFB0300601);辽宁省“兴辽英才计划”项目(LYC1907143);中国科学院战略重点研究项目(XDC04000000);辽宁省自然科学基金(2020-MS-008)。

摘　　要：利用原子探针层析技术(APT)对含1.4 mass%Cu的低合金高强度钢(High strength low alloy,HSLA)在450℃回火2~100 h后的富Cu团簇进行了表征,并对富Cu团簇的粗化行为及其强化行为进行了定量分析,通过拉伸实验测定了实验钢的力学性能。APT结果表明:随着回火时间的延长,富Cu团簇的等效半径逐渐增加、数量密度逐渐降低。富Cu团簇的粗化系数k,由回火2~10 h的1.9 nm^(3)/h,减小为50~100 h时的0.27 nm^(3)/h,导致富Cu团簇粗化速率下降。回火过程中,析出的富Cu团簇通过与位错的交互作用,显著提高了1.4Cu钢的屈服强度,回火2~10 h时后实验钢出现了一个屈服强度约为1076 MPa和伸长率约为19%的平台,表明实验钢具有良好的强塑性匹配。Cu-rich clusters of high strength low alloy(HSLA)steel containing 1.4 mass%Cu after tempering at 450℃for 2-100 h were characterized by atomic probe chromatography(APT),and the coarsening and strengthening behaviors of the Cu-rich clusters were quantitatively analyzed.The mechanical properties of the experimental steel were studied by tensile test.The APT results show that with the increase of tempering time,the equivalent radius of the Cu-rich clusters increases and the quantity density decreases.The coarsening coefficient(k)of the Cu-rich clusters decreases from 1.9 nm^(3)/h after tempering at 450℃for 2-10 h to 0.27 nm^(3)/h after tempering at 450℃for 50-100 h,which leads to the decrease of coarsening rate of the Cu-rich clusters.During tempering,the yield strength of the experimental steel is significantly improved by the interaction between the precipitated Cu-rich clusters and dislocations.After tempering at 450℃for 2-10 h,a platform with yield strength of 1076 MPa and elongation of 19%is found in the experimental steel,which indicates the experimental steel has good strong plastic matching.

关 键 词：HSLA钢 回火时间 富Cu团簇 粗化行为 强塑性 

分 类 号：TG142.3[一般工业技术—材料科学与工程]