Ultrasonic C-scan imaging and analysis of the mechanical properties of resistance spot-welded joints of stainless steel. Issue 3 (3rd July 2017)

• Record Type: Journal Article
• Authors: Sun, Xinyu; Zeng, Kai; He, Xiaocong; Zhang, Long
• Is Part Of: Nondestructive testing and evaluation. Volume 32:Issue 3(2017)
• Page Start: 242
• Page End: 254
• Publication Date: 2017-07-03
• Subjects: Spot-welded joint -- C-scan image -- A-scan signal -- mechanical properties; Non-destructive testing -- Periodicals; 620.112705
• DOI: 10.1080/10589759.2016.1241251
• Languages: English
• ISSNs: 1058-9759

Abstract

Abstract: The quality of spot-welded joints of 1 mm-thick SUS304 stainless steel sheets was investigated using scanning acoustic microscopy. C-scan images were used to characterize the weld evolution characteristics of welds formed under different welding parameters, and A-scan signals of feature regions were collected and analysed. The mechanical properties of the spot-welded joints were described in terms of the peak load, failure energy, failure mode and the failure displacement. The results illustrate that C-scan images can provide information about the internal state of spot-welded joints. The A-scan signals in different feature regions were distinct from each other, and three regions in the spot-welded joints were distinguished on the basis of the A-scan signals and the C-scan images: the weld nugget zone, the heat-affected zone and the fusion zone. When the supply pressure was 0.15 MPa, both over-burn defects and splash defects were observed; when the welding current was greater than 8 kA, only splash defects were observed. The peak load, the failure energy and the failure displacement tended to first increase and then decrease with increasing welding current and increasing supply pressure.