核级IN718高温合金中混晶原因及其对力学性能的影响  

Formation of Mixed Grains in Nuclear Grade IN718 Superalloy and Its Effect on Mechanical Properties

作　　者：李奥迪 梁田[2,3] 张学粮[4] 赵霞 王惠生[4] 陈嘉诚[4] 马颖澈 Li Aodi;Liang Tian;Zhang Xueliang;Zhao Xia;Wang Huisheng;Chen Jiacheng;Ma Yingche(School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China;Shi-changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;CAS Key Laboratory of Nuclear Materials and Safety Assessment,IMR(NMSA),Shenyang 110016,China;CGN Advanced Fuel Development Center,CGN Uranium Development Co.,Ltd,Yangjiang 529500,China)

机构地区：[1]中国科学技术大学材料科学与工程学院,辽宁沈阳110016 [2]中国科学院金属研究所师昌绪先进材料创新中心,辽宁沈阳110016 [3]中国科学院核用材料与安全评价重点实验室,辽宁沈阳110016 [4]中广核铀业发展有限公司中广核先进燃料研制中心,广东阳江529500

出　　处：《稀有金属材料与工程》2024年第3期736-747,共12页Rare Metal Materials and Engineering

摘　　要：通过设计不同初轧温度及变形量,研究了不同热轧工艺参数及轧后热处理对核级718合金组织和拉伸性能的影响。结果表明,在初轧温度低于1150℃且热变形量低于90%的条件下,组织中出现大量拉长晶,并降低合金的延伸率;当初轧温度达到1150℃或热变形量达到90%时,可以得到均匀的等轴晶组织。轧后板材进行990℃固溶处理后,δ相析出并对晶界产生钉扎作用,形成了混晶显微组织且在标准时效处理后在315℃时屈服强度、抗拉强度均值可达到1050 MPa和1238 MPa,断后伸长率高达26%;当进行1020℃固溶处理后可得长大的等轴晶粒,标准时效处理后在315℃时屈服强度、抗拉强度均值可达到985 MPa和1175 MPa,断后伸长率高达29%,显示出良好的强韧性。The effects of different hot rolling parameters and post-rolling heat treatment on the structures and tensile properties of nuclear grade 718 alloys were investigated by designing different initial rolling temperatures and deformation amounts.The results show that when the initial rolling temperature is below 1150℃and the heat deformation amount is lower than 90%,a large number of elongated grains appear in the structure and the elongation of the alloy is reduced;when the initial rolling temperature is 1150℃or the heat deformation amount reaches 90%,a uniform equiaxed grain structure can be obtained.After the solid solution treatment at 990℃of the rolled plate,δphases are precipitated and pinned to grain boundaries,and a mixed grain microstructure forms.The average values of yield strength and tensile strength at 315℃after standard aging treatment can reach 1050 MPa and 1238 MPa,respectively,and elongation is up to 26%;Upon solid solution treatment at 1020℃,the grown equiaxed grains are obtained,whereas the average yield strength and tensile strength at 315℃can reach 985 MPa and 1175 MPa after standard aging treatment,respectively,and the elongation is up to 29%,and the alloy exhibits good strength and toughness.

关 键 词：核级718合金 拉长晶 混晶 拉伸性能 

分 类 号：TG146.15[一般工业技术—材料科学与工程]