کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
829404 1470341 2014 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Low cycle fatigue properties of friction stir welded joints of a semi-solid processed AZ91D magnesium alloy
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی (عمومی)
پیش نمایش صفحه اول مقاله
Low cycle fatigue properties of friction stir welded joints of a semi-solid processed AZ91D magnesium alloy
چکیده انگلیسی


• Sound friction stir welded joints with fine grains in the nugget zone are achieved.
• Fatigue life of joints can be described by the Basquin and Coffin-Manson equations.
• Unlike the extruded magnesium alloys, the hysteresis loops of joints are symmetrical.
• The joints are observed to fail in the base metal rather than in the nugget zone.

A semi-solid processed (thixomolded) Mg–9Al–1Zn magnesium alloy (AZ91D) was subjected to friction stir welding (FSW), aiming at evaluating the weldability and fatigue property of the FSW joint. Microstructure analysis showed that a recystallized fine-grained microstructure was generated in the nugget zone (NZ) after FSW. The yield strength, ultimate tensile strength, and elongation of the FSW joint were obtained to be 192 MPa, 245 MPa, and 7.6%, respectively. Low-cycle fatigue tests showed that the FSW joint had a fatigue life fairly close to that of the BM, which could be well described by the Basquin and Coffin-Manson equations. Unlike the extruded magnesium alloys, the hysteresis loops of FSW joint of the thixomolded AZ91D alloy were basically symmetrical, while the non-linear or pseudoelastic behavior was still present. The FSW joint was observed to fail in the BM section rather than in the NZ. Fatigue crack initiated basically from the pores at or near the specimen surface, and crack propagation was mainly characterized by fatigue striations along with the presence of secondary cracks.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Materials & Design - Volume 56, April 2014, Pages 1–8
نویسندگان
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