电弧超声对09MnNiDR钢焊接接头冲击性能的影响  

Arc-excited ultrasonic welding to improve the quality of 09MnNiDR joints

作　　者：吴敏生[1] 张雁军[1] 李路明[1] 郝红伟[1] 

机构地区：[1]清华大学机械工程系,北京100084

出　　处：《清华大学学报（自然科学版）》2006年第2期161-164,共4页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金资助项目(50375080)

摘　　要：通过调制电弧激发出超声并应用于09M nN iDR钢的埋弧自动焊过程。采用常规焊接工艺参数,并加入不同频率的电弧超声进行焊接工艺评定。金相分析表明,在电弧超声作用下,焊缝结晶组织明显细化,焊缝区针状铁素体增加。冲击实验表明,接头的低温冲击韧性提高。尤其是在50 kH z超声作用下,-70℃下焊缝区和热影响区冲击韧性值较未加入超声时均提高了近50%,相应的断口扫描电子显微镜(SEM)分析表明接头由解理断裂转变为韧性断裂。电弧超声还可降低接头对焊接热输入的敏感性,提高生产效率。实验证明电弧超声是提高低温钢焊接接头性能的一种有效的方法。The electrical arc welding frequency was modulated to excite ultrasonic waves ,in submerged arc welding of cryogenic 09MnNiDR steel. The arc excited ultrasonic welding procedure was evaluated by comparing conventional welding techniques with arc excited ultrasonic welding at different frequencies. Metallographic analyses show that the ultrasonic welding significantly refines the grains with more acicular ferrite appears in the fusion zone. Impact tests show that the ultrasonic welding also enhances the joint impact toughness. At 50 kHz, the impact toughness at - 70 ℃ was improved by nearly 50% both in the fusion zone and in the heat affected zone compared with welding without ultrasonic excitement. Scan electron microscope （SEM） fractography shows that fractures changes from cleavage fractures without ultrasonic to gliding fractures With ultrasonic welding. The arc-excited ultrasonic welding also reduces the welding line-energy sensitivity and improves production efficiency.

关 键 词：焊接自动化技术 电弧超声 低温钢 晶粒细化 冲击韧性 

分 类 号：TG409[金属学及工艺—焊接]