Ultrasonic Evaluation at the Interface of Aluminum/Steel Obtained by TIG Welding

Malaysia International NDT Conference and Exhibition 2018

Ahsan, Qumrul^1 ; Kato, Hiroshi^2

Carbon Research Technology Group, Advanced Manufacturing Centre, Faculty of Manufacturing Engineering, Universiti Teknikal Malaysia Melaka, Hang Tuah Jaya, Durian Tunggal, Melaka

76100, Malaysia^1

Department of Mechanical Engineering, Division of Mechanical Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama-city, Saitama

338-8570, Japan^2

关键词: Alternate currents;    Direct current straight polarity mode;    Gas tungsten arc welding process;    Intermediate phase;    Metallographic analysis;    Nondestructive assessment;    Scanning Acoustic Microscopy;    Ultrasonic evaluation;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/554/1/012010/pdf
DOI  :  10.1088/1757-899X/554/1/012010

来源: IOP

【 摘 要 】

Aluminum filler (Al-5%Si) is bonded on steel substrate by gas tungsten arc welding process under different current setting conditions. After welding a thorough metallographic analyses using optical and scanning electron microscopy were carried out to observe Al-Steel interface. Ultrasonic measurements by immersion and scanning acoustic microscopy were made to characterise the bond at Al-Steel interface. The ultrasonic wave reflected from the Al-Steel interface clearly indicated the more debonded area when the welding current is changed from direct current straight polarity (DCSP) mode to alternate current high frequency (ACHF) or the welding current in case of current for DCSP mode is reduced. This may be attributed either adequate amount of oxides along with intermediate phase make the bond interface rough and uneven due to introduction of ACHF mode or debonded areas are higher due to lower heat input when the current reduced to 125 amps from 150 amps in DCSP mode. Whereas smooth and even bond interface due to uniform heat input resulted stable Al-Steel interface and the mapping of bonded area by ultrasonic measurement showed spectrum of minimum peak for using current of 150 amps in DC mode. Thus the non-destructive assessments of interface between dissimilar materials through ultrasonic measurements could be important tools for evaluating the state of the bond.