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论文类型：期刊论文

发表时间：2020-01-01

发表刊物：JOURNAL OF MANUFACTURING PROCESSES

收录刊物：EI、SCIE

卷号：49

页面范围：385-396

ISSN号：1526-6125

关键字：Aluminum alloy; Uncoated low carbon steel; Refilled friction stir spot welding; Mechanical property; Microstructure

摘要：Aluminum alloy and steel hybrid structures offer clear advantages in weight reduction and energy conservation for the automotive industry. This paper exhibits sound refilled friction stir spot welded joints between the aluminum alloy and ST16 steel sheets with the maximum tensile/shear and cross-tension fracture loads of 3745 N and 1073 N, respectively. All samples failed through the interface of aluminum alloy/steel joints during tensile/shear test and cross-tension test. The microstructure and fracture mode of the joints were studied with the scanning electron microscope, electro-probe microanalyzer and X-ray diffraction. For the joints where the sleeve had not plunged into the ST16 steel, the effect of the sleeve plunging depth and rotation speed on the tensile/shear fracture load cannot be identified, as an intermetallic compounds layer formed between Al and Fe, which was almost uniform across the interface. The mechanical performance of joints increased dramatically when the sleeve plunged into the ST16 steel because of metallurgical bonding and mechanical interlocking in the sleeve-affected zone. However, this process caused considerable wear to the tool and shortened its service life. The bonding mechanism was investigated by studying joints between the aluminum alloy and galvanized steel for the same welding parameters.