Study on the Friction Stir Welding of magnesium alloy process using a CNC milling machine.

• Main Authors: CHIEN,HUNG-TSANG, 簡宏蒼
• Other Authors: LIN,HSUAN-LIANG
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/mnf74a

碩士 === 國立高雄師範大學 === 工業科技教育學系 === 105 === A CNC milling machine was used to conduct the friction stir welding butt-joint of 6061-T aluminum alloy with AZ31 magnesium alloy and AZ31 magnesium alloy, the fixture specially designed for friction stirrer and the friction stir bar were designed. The experimental parameters in the process include the feed force and the tool shape of the friction stir bar. When finished welding, take a part of test piece then taken to mounting, after grinding and polishing, observe the OM structure, and test the tensile strength of the test piece, after the test results to determine whether the friction stir process is suitable for CNC milling machine. Using of materials SKH51 stir bar will be in the process of a large number of losses in the aluminum alloy and magnesium alloy process; and the use of different parameters, will affect the flow of materials, and tensile strength. After process, the test piece to produce separation, fixture can’t hold the alloy complete, needs to improve the clamping method. In the magnesium alloy process, the improvement of the clamping alloy, the welding has improve; stir bar convex angle of 8∘, shoulder diameter of 20 mm is the best design in this experiment. When the rod feed rate is fixed at F160, the tensile strength of the speed of 1800RPM higher than 2300rpm. The rupture of the rupture of the organization showed a crack in the direction of the ladder expansion, this phenomenon more like transgranular in the tensile fracture surface. The damage point of the organization in the form of layered stacking different, so the rupture method is along the stirring rod forward edge to the break point in the bead to extend the past, this rupture method for the destruction of the intergranular. AZ31 magnesium alloy in the friction stir welding process, will form two characteristics of mixed rupture.