【作者】 庞铭； 虞钢； 郑彩云； 宁伟建； 王立新；

【Author】 Pang Ming~①YuGang~②Zheng Caiyun~②NingWeijiang~②WangLixin~②(①China North Engine Research Institute,Datong,P.R.China;②Chinese Academy of Sciences,Beijing,P.R.China)

【机构】 中国北方发动机研究所； 中国科学院力学研究所；

【摘要】 研究了镍基高温合金K418与合金钢42CrMo异种金属激光焊接焊缝缺陷的形成机制。通过光学显微镜观察了焊缝的宏观缺陷;通过扫描电镜观察了焊缝的微观缺陷,并使用能谱仪测量了焊缝缺陷处和枝晶核的成份。研究结果表明:K418和42CrMo异种金属激光焊接焊接参数选择不合理,焊缝易形成塌陷、气孔和裂纹等缺陷;焊缝区域的热裂纹是和焊接过程晶界形成的低熔物密切相关;在焊接试样被焊透的条件下,提高焊接速度可以避免焊缝塌陷;通过优化焊接过程保护气流量和维持激光深熔焊接过程匙孔的稳定性可以抑制焊缝区域气孔的产生。更多还原

【Abstract】 The mechanism of defect formation during laser dissimilar welding of K418 and 42CrMo is studied.The macroscopic defect of weld seam is observed by optical microscopy.Microcosmic defect of weld seam is observed by scanning electron microscopy.The detail chemical compositions of defect and interdendritic regions are measure by energy dispersive spectrometer.Results show defect of excessive penetration,gas pore and crack can form with improper welding parameters.Excessive penetration can be avoided by increasing welding velocity.Gas pore can be controlled by optimization welding parameters and keeping steady keyhole.更多还原