火焰喷熔涂层与焊接接头性能研究  

Spray Fused Coating and Properties of Welded Joints

作　　者：赵小辉[1] 王东坡[1] 邓彩艳[1] 王颖[1] 徐艳[1] 

机构地区：[1]天津大学材料科学与工程学院天津市现代连接技术重点实验室,天津300072

出　　处：《天津大学学报》2012年第3期254-258,共5页Journal of Tianjin University(Science and Technology)

基　　金：国家自然科学基金资助项目(50805102)

摘　　要：采用Ni60A合金粉末对Q235B钢十字焊接接头进行了喷熔修形处理.通过对涂层和焊缝的金相、扫描电镜、能谱等分析,研究了涂层与基体间的冶金结合情况,发现涂层组织致密、非金属夹杂物少、孔隙率低,与基体实现了良好的冶金结合.喷熔涂层本身的强度直接影响着十字焊接接头低周疲劳强度的大小.为此,通过有限元模拟和拉伸试验测定了涂层的抗开裂力值的大小.结果表明:当应力值为350,MPa时涂层开裂,说明涂层自身强度较高.在应力比为0.1、平均应力为186,MPa的情况下,喷熔接头的低周疲劳寿命均超过13,000周次以上,并且断裂位置均在母材.Cruciform welded joints of Q235B steel was processed through modification of spray fusing with nickel- base alloy powder of Ni60A. The condition of metallurgical combination between coating and weld was examined by metallographical, SEM and energy spectrum analysis. Little non-metallic inclusion and lower porosity were found in the coating. The coating and weld achieved good metallurgical combination. The intensity of spray coating directly influences low-cycle fatigue strength of welded joints. Therefore, the cracking resistance force value was measured through simulation and tensile test. The result showed that the coating crazed when stress value was 350 MPa, which indicated that strength of coating itself was higher. Low-cycle fatigue life of spray fused welded joint was over 13 000 cycles under the condition of stress ratio being 0. 1 and average stress being 186 MPa, and fracture positions were at the base material.

关 键 词：喷熔修形 低周疲劳 冶金结合 

分 类 号：TG405[金属学及工艺—焊接]