矿山支架用高强钢焊接工艺研究  

Study on welding technology of high strength steel for mine support

作　　者：杨阳 YANG Yang(China Coal Research Institute Co.,Ltd.,Beijing 100013,China)

机构地区：[1]煤炭科学技术研究院有限公司,北京100013

出　　处：《焊接技术》2021年第8期40-43,I0015,共5页Welding Technology

基　　金：国家重点研发计划(2017YFB1103603);辽宁省自然科学基金计划重点项目(20180510030)。

摘　　要：低合金调质高强钢因具有强度高、塑韧性好的特点而被广泛用于矿山机械部件中。为了提高焊接接头的质量,延长焊接结构的使用寿命,通过增大热输入的工艺,系统地研究了焊接接头的组织与力学性能。结果表明:焊接接头断口为典型的韧性断裂,随着热输入的增大,焊缝中的针状铁素体含量增多,焊缝的力学性能逐渐提升,当热输入为13.7 kJ/cm时,焊缝的拉伸性能和冲击性能均达到最佳,焊接接头的抗拉强度达到最高为865.32 MPa,断面收缩率为42.96%,抗拉强度为母材抗拉强度的80%以上;当热输入继续增大时,焊缝金属的力学性能因晶粒尺寸的增大而降低,铁素体的针状形态削减,断裂方式逐渐转为脆性断裂。Low alloy quenched and tempered high-strength steel is widely used in mining machinery parts because of its high strength and good plastic toughness. In order to improve the quality of welded joints and prolong the service life of welded structures, the organization and mechanical properties of welded joints had been systematically studied by increasing the welding heat input process. The results showed that the fracture of the welded joint was a typical ductile fracture. With the increase of welding heat input, the content of acicular ferrite in the weld increased, and the mechanical properties of the weld were improved gradually. When the welding heat input was 13.7 kJ/cm, the tensile properties and impact properties of the welds were the best, the tensile strength of the welded joints was 865.32 MPa,the reduction of area was 42.96%, and the tensile strength was more than 80% of the tensile strength of the base metal.When the welding heat input continued to increase, the mechanical properties of the weld metal would decrease due to the increase in grain size, the needle-like shape of ferrite would be reduced, and the fracture mode would turn to brittle fracture gradually.

关 键 词：高强钢 热输入 微观组织 拉伸性能 冲击韧性 

分 类 号：TG422[金属学及工艺—焊接]