• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>HTD-vol.376-2; ASME(American Society of Mechanical Engineers) International Mechanical Engineering Congress and Exposition; 20051105-11; Orlando,FL(US) >TRANSPORT PHENOMENA AND THE ASSOCIATED HUMPING FORMATION IN LASER WELDING
【24h】

TRANSPORT PHENOMENA AND THE ASSOCIATED HUMPING FORMATION IN LASER WELDING

机译：激光焊接中的运输现象和相关的蜂巢形成

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Humping is a frequently observed welding defect in laser welding which is caused when the welding speed exceeds a certain limit while the other welding conditions remain unchanged. Humping is characterized by the appearance of unsmooth and discontinuity of humps at the surface of the weld. The formation of humping is generally understood to be caused by the complex heat transfer and melt flow in a high speed welding process. However, so far the fundamental mechanisms causing humping are not fully understood, and research on determining the onset of humping has been based on the "trial-and-error" procedure. In this paper, mathematical models previously developed by the authors for the transport phenomena in laser welding have been extended to investigate the formation of the humping defect. In this study, the transient heat transfer and melt flow in the weld pool during the keyhole formation and collapse, and melt solidification are calculated for a 3-D moving laser welding. Different humping patterns have been predicted by the present study in different laser power levels and welding speeds. From the present study, it was found that the formation of humping in laser welding is caused by the interplay between two important factors: a) the strong liquid metal flow in the real part of the keyhole induced mainly by the laser recoil pressure and b) the rapid solidification rate of the liquid metal. The humping pattern can be well explained by the calculated melt flow and the solidification process.
机译：隆起是在激光焊接中经常观察到的焊接缺陷，当焊接速度超过一定极限而其他焊接条件保持不变时，则会引起焊接缺陷。隆起的特征是在焊缝表面出现不光滑和隆起的不连续性。通常认为起峰的形成是由高速焊接过程中复杂的传热和熔体流动引起的。但是，到目前为止，引起驼峰的基本机制还没有被完全理解，并且关于确定驼峰开始的研究已经基于“试错法”程序。在本文中，作者先前为激光焊接中的传输现象开发的数学模型已得到扩展，以研究驼峰缺陷的形成。在这项研究中，对于3-D移动激光焊接，计算了在小孔形成和塌陷期间在熔池中的瞬态热传递和熔体流动以及熔体凝固。本研究已经预测了在不同的激光功率水平和焊接速度下不同的驼峰模式。从本研究中发现，激光焊接中的隆起的形成是由两个重要因素之间的相互作用引起的：a）主要由激光反冲压力引起的锁孔实部中大量液态金属流动，以及b）液态金属的快速凝固速度。通过计算出的熔体流动和凝固过程可以很好地解释驼峰模式。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号