State Key Laboratory of Solidifi cation Processing,Northwestern Polytechnical University,Xi’an 710072,China;
Shaanxi Key Laboratory of Friction Welding Technologies,Northwestern Polytechnical University,Xi’an 710072,China;
AVIC Manufacture Technology Institute,Beijing 100024,China;
Submillimeter; Plunge; depth; Mechanical; properties; Friction; stir; lap; welding;