Evaluation of Residual Stresses in Carbon Steel Weld Joints by Ultrasonic L cr Wave Technique
Evaluation of Residual Stresses in Carbon Steel Weld Joints by Ultrasonic L cr Wave Technique
复制标题
DOI：
--
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
A. Joseph;P. Palanichamy;T. Jayakumar
中科院分区：
文献类型：
--
作者：
A. Joseph;P. Palanichamy;T. Jayakumar
基于超声波的残余应力测量是无损的，并提供表面/亚表面和体积残余应力的定量估计。超声技术的基本原理是声弹性，即超声速度的应力依赖性。三对20 mm厚的低碳钢焊接接头采用手动金属电弧焊工艺制造，具有三个略微不同的热输入（最佳，略低于最佳和高于最佳），并用于研究。本研究采用临界折射纵向（L cr）超声波技术。本文详细介绍了超声波Lcr波残余应力测量技术的发展和碳钢焊接接头表面/亚表面残余应力的定量估算。研究表明，较低的拉伸残余应力值在焊接接头使用略低于最佳加热输入，而不是残余应力值在焊接接头使用最佳和略高于最佳热输入。已开发的超声波Lcr波技术被发现是非常敏感的，即使是在焊接过程中所采用的热输入略有不同引起的焊接接头上的残余应力分布的微小变化。
Ultrasonic based residual stress measurements are nondestructive and offer quantitative estimation of surface/sub-surface and bulk residual stresses. The underly-ing principle of the ultrasonic techniques is the ‘acoustoelas-ticity’ i.e. the stress dependence of ultrasonic velocity. Three pairs of 20 mm thick low carbon steel weld joints were fabricated using manual metal arc welding process with three marginally different heat inputs (optimum, marginally below optimum and above optimum) and used in the study. Critically refracted longitudinal (L cr ) ultrasonic wave technique was employed for this study. This paper gives the details of development of ultrasonic L cr wave based technique for residual stress measurements and the quantitative estimation of surface/sub-surface residual stresses in carbon steel weld joints. The study indicates lower value of tensile residual stress in weld joints made using marginally below optimum heatinputwhencomparedtotheresidualstressvaluesinweld joints made using optimum and marginally above optimum heat inputs. The developed ultrasonic L cr wave technique is found to be very sensitive even to the small variations in the residual stress profiles across the weld joints induced by marginally different heat inputs employed during welding.