摘要
为了研究Ni、Cr、Mo、Ti、V元素对X80管线钢熔敷金属显微组织和力学性能的影响,设计了5种化学成分的实心焊丝,并用其对X80管线钢进行MIG焊焊接.经过光学显微镜、电子扫描显微镜分析及力学性能试验,对熔敷金属的显微组织、力学性能进行了研究.结果表明:随着碳当量的增加,熔敷金属的拉伸性能不断提升;Ni含量低于1.0%时,随着Ni含量的增加,针状铁素体比例略增加,而先共析铁素体尺寸发生粗化;Ti、V微合金元素含量的增加,可增加熔敷金属针状铁素体的长宽比,使M-A组元尺寸显著减小,从而屈服强度保持在612 MPa,-20℃下冲击吸收功可达141 J;当Cr、Mo元素含量提高至0.57%时,等轴铁素体被成排的贝氏体取代,且包含大量原奥氏体晶界,使得冲击韧性急剧恶化.
To study the effects of the Ni,Cr,Mo,Ti,and V elements on the microstructure and mechanical properties of the deposited metal of X80 pipeline steel,solid welding wires with five chemical compositions were designed and used for the MIG welding of X80 pipeline steel.The microstructure and mechanical properties of the deposited metal were studied using an optical microscope,scanning electron microscope analysis,and mechanical property test.The results showed that the tensile properties of the deposited metal can be continuously improved with the increase in the carbon equivalent.When the Ni content was lower than 1.0%,with the increase in the Ni content,the acicular ferrite proportion slightly increased,whereas the size of the proeutectoid ferrite was coarsened.The increase in the contents of the Ti and V microalloying elements increased the aspect ratio of the deposited metal acicular ferrite,which can significantly reduce the size of the martensite-austenite(M-A)component.Thus,the yield strength could remain at 612MPa,and the impact absorption energy at-20℃reached 141 J.When the content of the Cr and Mo elements increased to 0.57%,the equiaxed ferrite was replaced by rows of bainite and had a large number of prior austenite grain boundaries,which made the impact toughness deteriorate sharply.
作者
巴凌志
利成宁
冯兆龙
唐新新
王泽龙
邸新杰
Ba Lingzhi;Li Chengning;Feng Zhaolong;Tang Xinxin;Wang Zelong;Di Xinjie(School of Materials Science and Engineering,Tianjin University,Tianjin 300350,China;Tianjin Key Laboratory of Advanced Joining Technology,Tianjin 300350,China;Chengdu Advanced Metal Materials Industrial Technology Institute Co.,Ltd.,Chengdu 610303,China)
出处
《天津大学学报(自然科学与工程技术版)》
EI
CAS
CSCD
北大核心
2023年第11期1187-1194,共8页
Journal of Tianjin University:Science and Technology
基金
国家自然科学基金资助项目(52074191).
关键词
X80管线钢
熔敷金属
合金化
显微组织
性能
X80 pipeline steel
deposited metal
alloying
microstructure
property