کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5007174 1461608 2017 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Investigation of welding crack in micro laser welded NiTiNb shape memory alloy and Ti6Al4V alloy dissimilar metals joints
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی برق و الکترونیک
پیش نمایش صفحه اول مقاله
Investigation of welding crack in micro laser welded NiTiNb shape memory alloy and Ti6Al4V alloy dissimilar metals joints
چکیده انگلیسی
Dissimilar metals of NiTiNb shape memory alloy and Ti6Al4V alloy with a same thickness of 0.2 mm were joined by micro laser welding. The effect of laser power on crack sensitivity of the weld was investigated. The results show that full penetrated welds are obtained when the laser power of 7.2 W is used, many cracks are observed in the weld. With increasing the laser power to 12 W, the number of all cracks and cracking width first increase and then decrease. By XRD analysis, three different kinds of Ti2Ni, NbNi3 and AlNbTi2 intermetallic compounds are found in the weld. According to the formation enthalpy and binary phase diagram, brittle Ti2Ni phase with more contents is existed in the weld due to final solidification, and which is the main reason of crack formation along with large stress concentration. Moreover, the welding cracks like the weld center longitudinal solidification cracks, weld metal toe transversal liquid cracks, heat-affected-zone hot cracks and crater cracks are classified in the laser welded joints. A brittle cleavage fracture with cleavage planes and river patterns in the joints is presented from the fracture surface.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Optics & Laser Technology - Volume 91, 1 June 2017, Pages 197-202
نویسندگان
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