Research On The Technology And Structure Property Of 5A05 Al Alloy Friction Stir Welding

In this paper, the Friction Stir Welding (FSW) technology of 5A05 Aluminum Alloys which are studied. It mainly introduces the basic foundation of FSW, and its advantages and disadvantages, its present study in home and abroad and its developing prospect are also been studied. We mainly study the main parameters (include rotational speed, welding speed, the pressure of the shoulder)of FSW which affect the quality of the joint. As to5A05 aluminum alloy, we have done such experiment as technology experiment, tensile test, bending test, metallography experiment, hardness experiment and etc. Experimental results shows that if the welding parameters are optimal, good appearance welds are achieved, otherwise if the welding parameters are not good ,fin and groove defects will appear . It also showed that the mechanical properties of the joints are significantly affects by the welding parameters. and also found some relations between the joints mechanical properties and the parameters. When other parameters are constant ,the mechanic properties of weld increases with the improvement of welding speed, then attain a maximum value ,then the properties will deteriorate with the further increase of the parameter. So are the relations of joints mechanical properties and the ratio(welding speed/rotational speed).When the parameter is optical ,the tensile property of weld can attain 90 percent of that of the base metal, and its elongation can attain 80 percent of than of the parent metal. It analysis tensile stress with differentω/ν,and relationship betweenωandσwith theνis 50 mm/min,100 mm/min, 200 mm/min. It summary the microstructure change law of test plates with different welding parameter, and the distribution of hardness. The study show that, when V is 50mm/min,theσis increasing with theωincreasing, then it decreases later; when the V is 100mm/min,theσis increasing when theωincreasing;when V is 200mm/min,the law can not be gotten. By observing the metallographic phase, we can know that the crystal particle in the WNZ is smaller than it in the BM; from the micro-hardness fig, we can know that the lowest hardness is in the HAZ or TMAZ.