The Study Of Fluid Simulation For Semi-solid Stirring Brazing Aluminium Matrix Composites

In this paper, the professional computer numerical simulation software is used tosimulate the processing of semi-solid stirring brazing in air. Two-dimensional numericalcalculation model is established, which the flow of filler metal is looked as viscous,laminar and incompressible Newtonian fluid. The stirring tool is looked as a rotating typeof entity, by setting velocity inlet boundary conditions to realize the effect of weldingplatform moving. This article mainly discusses the influence of four kinds of weldingparameters in flow field through the calculation model, which are welding temperature,welding speed, stirring rotation speed and stirring tool size respectively. At the same timethe actual welding experiment is implemented with the four kinds of welding parameters.Through computer numerical simulation to get the distribution of the flow field in the weldfiller metals, which predict and explain the actual situation, at the same time through theactual welding experiment to verify the result of the computer numerical simulation.Finally, based on the computer numerical simulation, an optimized semi-solid stirringbrazing aluminum matrix welding process is established.The weld interface of macro-micro morphology and mechanical properties of theweld joint can be explained basically by the computer numerical simulation model. At thesame time, the truth welding experiments can verify the results of computer numericalsimulation basically.The result of computer numerical simulation shows that the lower weldingtemperature, the more obvious effect on the substrate surface. If the temperature is too low,it will affect the forming of weld filler metals; The welding speed influence the distributionuniformity of force filed on the both sides of the interface but has less influence on the sizeof interface force field. The lower welding speed will make the more uniform distributionat both sides; Stirring rotation speed mainly influence the quantity of rotation force fieldand also the uniform distribution of force field at both sides of the interface. The higherstirring rotation speed, the greater force filed, and more uniform distribution at both sides;The size of stirring tool mainly influence the intensity of the effect of rotation force fieldmainly, the bigger it is, the greater force filed there is.By the model of computer numerical simulation, the reasonable welding parameterwill be obtained as follows: T=470℃,v=1.25mm/s, ω=5440rpm and D=1.9mm. Under the welding parameter, the good welding joint will be obtained, because the force fieldat the sides is higher and more uniform distribution. The number of shear stress can bereached101MPa by actual brazing experiment, slightly higher than the parent materials. Atthis time, not only good performance and slinky shape will be got, but also improve theoperability of welding and welding efficiency, etc.