Several variations of friction stir tools were used to investigate the effects on the joint strengths of dissimilar friction stir lap welds. In the present lap weld configuration the top sheet was a 2.32 mm thick Mg (AZ 31) alloy. The bottom sheet consisted of two different steels, a (i) 0.8 mm thick electro-galvanized (EG) mild steel, or a (ii) 1.5 mm thick hot dip galvanized (HDG) high strength low alloy (HSLA) steel. Initially the tool shape was modified to accommodate the material, at which point the tool geometry was fixed. With a fixed tool geometry an additional feature was added to the pin bottom on one of the tools by incorporating a short hard insert, which would act as a stronger bottom sheet cutter. The effects of such modification on the unguided lap shear strength, and associated microstructural changes are discussed in this study.
Revised: December 30, 2011 |
Published: April 25, 2011
Citation
Jana S., Y. Hovanski, G.J. Grant, and K.F. Mattlin. 2011.EFFECT OF TOOL FEATURE ON THE JOINT STRENGTH OF DISSIMILAR FRICTION STIR LAP WELDS. In Friction Stir Welding and Processing VI: Proceedings of a symposia sponsored by the Shaping and Forming Committee of the Materials Processing & Manufacturing Division of TMS (The Minerals, Metals & Materials Society) Held during the TMS 2011 Annual Meeting & Exhibition February 27-March 3, 2011, San Diego, California, edited by R Mishra, MW Mahoney, Y Sato, Y Hovanski and R Verma, 205-211. Hoboken, New Jersey:John Wiley & Sons, Inc.PNNL-SA-75817.doi:10.1002/9781118062302.ch25