Welded Joint Nonpenetration and Slag Inclusion Evaluation Based on MMM Signal Characteristic

Abstract:

The metal magnetic memory (MMM) technology, a new nondestructive testing (NDT), has potentials of quantitative evaluation on welded joint defects. This paper investigates MMM signal quantitative characteristic of welded joint defects. Steel Q235 welded joint specimens, prefabricated with nonpenetration and slag inclusion, have been scanned by MMM testing instrument at 0kN, 150kN and 230kN tension loads on tensile machinery. For the nonpenetration specimens, MMM peak amplitude ΔHp and the peak width D adds with the increasing of tensile load, but gradient K varies a little. As for the slag inclusion specimens, the ΔHp and K enhances along with tensile load increasing, but the D varies a little. The X-ray testing results at 0kN, 150kN and 230kN tension loads show the validity of MMM signal characteristic. This means the feasibility of the weld qualitative and quantitative evaluation based on MMM method.

• Periodical: Advanced Materials Research (Volumes 189-193)
• Pages: 3355-3358
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.189-193.3355
• Online since: February 2011
• Authors: Hai Yan Xing, Li Hong Zhang, Cheng Xu, Xin Yu Chen
• Keywords: Characteristic Signal, Magnetic Memory Testing, Welded Joint Defect

References

[1] Dubov A.A. Study of metal properties using metal magnetic memory method [A]. 7th European Conference on Non-destructive Testing [C]. Copenhagen. (1997).

[2] Doubov A.A. Diagnostics of metal items and equipment by means of metal magnetic memory [A]. ChS NDT 7th Conference on NDT and International Research Symposium [C]. Shantou, China. (1999).

[3] Bin Hu: Applied Research of Magnetic Memory Method(MMM) on Amusement Devices[A]. 17th WorldConferenceonnondestructive testing[C]. Shanghai, China. (2008).

[4] Yuan Li, Youfu Li, Qing Lin Wang and De Xu: Measurement and defect detection of the weld bead based on online vision inspection[J]. IEEE Transactions on Instrumentation and Measurement. Vol. 59 (2010), pp.1841-1849.

DOI: 10.1109/tim.2009.2028222

[5] Jian Li, Xianqin Zhan and Shili Chen: An automatic flaw identification method for defect inspection of pipeline girth weld [A]. Proceedings of the Biennial International Pipeline Conference. IPC, Vol. 3 (2009), pp.175-178.

DOI: 10.1115/ipc2008-64273

[6] Pingzhou Cao, Jianfeng Chen and Wentao Zhao: Experimental investigation on tensile strength of butt welded joint post high temperatures[J]. China Welding (English Edition), Vol. 18 (2009), pp.21-26.

[7] Wikstrom Jenny and Nakajima Keiji: Application of a model for liquid inclusion separation at a steel-slag interface for laboratory and industrial situations[J]. Steel Research International. Vol. 79 (2008), pp.826-834.

DOI: 10.1002/srin.200806206