焊缝内部纵裂纹缺陷表面热特征研究

根据焊缝内部缺陷对内部热量扩散的影响,向焊缝局部表面注入热流,利用大型有限元分析软件ANSYS计算表面温度场分布,分析纵裂纹缺陷引起的表面温度场异常分布.不同长度、宽度及深度的裂纹,距加热面不同距离引起的表面温度场异常分布情况不同.文章重点研究了表面热特征与裂纹缺陷尺寸,缺陷位置及注入的热流密度的定量关系.本文工作可为实施红外无损检测提供方法,并为相关标准的制定提供依据.

Study on Surface Thermal Character of Fore and aft Crack Defect in the Weld

According to the theory that thermal expansion in the weld is affected by the defect in it,finite element analysis software ANAYS is used to compute the temperature distribution on surface and analyze the un-normal temperature distribution caused by fore-and-aft crack defect.Different un-normal temperature distribution is caused by the crack of different length,width and depth,which is in different position of weld.The emphasis is placed on the quantitative relationship between the dimension and position of defect,the surface thermal character and the consistence of heat flux imposed.This job can provide method for infrared non-destructive testing be used for the testing of crack in the weld and foundation for the establishment of exact and reliable testing standard.