Effect of welding parameters on semisolid stir welding of Mg-9Al-1Zn magnesium alloy
2016 (English)In: Transactions of Nonferrous Metals Society of China, ISSN 1003-6326, E-ISSN 2210-3384, Vol. 26, no 10, 2586-2594 p.Article in journal (Refereed) Published
Semisolid stir welding of AZ91 was investigated with focus on the joining temperature and rotational speed. An Mg-25% Zn interlayer was located between two AZ91 pieces and the system was heated up to the semisolid state of base metal and interlayer. The weld seam was stirred using a drill-tip at different joining temperatures and rotational speeds. Optical and scanning electron microscopes were employed to study microstructure, cavity formation, and segregation. Hardness profile and shear punch test were also employed to rank the welds based on their quality and homogeneity. Results showed that the lowest cavity content (2.1%) with the maximum ultimate shear strength (about 188 MPa) was obtained in weld with the joining temperature of 530 degrees C and the rotational speed of 1600 r/min. Low quality welds and a reduction of ultimate shear strength were observed at very high or low rotational speeds and joining temperatures. The process, in conclusion, produced close mechanical properties to those of the base metal and homogenous quality throughout the joint, when the intermediate temperature and rotational speeds were employed.
Place, publisher, year, edition, pages
2016. Vol. 26, no 10, 2586-2594 p.
Mg-Al-Zn alloy; mechanical stirring; semisolid stir welding
Manufacturing, Surface and Joining Technology
Research subject Production Technology; ENGINEERING, Manufacturing and materials engineering
IdentifiersURN: urn:nbn:se:hv:diva-10340DOI: 10.1016/S1003-6326(16)64384-4ISI: 000387378400007ScopusID: 2-s2.0-84994157783OAI: oai:DiVA.org:hv-10340DiVA: diva2:1057793