Dynamic Constitutive Model Of 5083 Aluminum Alloy And Finite Element Simulation On The Forming Process Of Innner-grooved Aluminum Tube

The inner-grooved tube is an efficient and energy-saving heat exchange tube,which is widely used in the refrigeration industry such as home appliances,automobile air conditioner.currently,the inner-grooved tube materials are mainly made of copper tubes which are widely used;however,aluminum and aluminum alloys have advantages such as smaller in gravity,lower in price compared to copper and copper alloys.Under the circumstances that copper prices have remained high for a long time and "aluminum replace copper" heat transfer technology has proven to be feasible,the process technology and production technology of inner-grooved copper tubes have been reduced to reduce the forming process and production costs of inner-grooved aluminum tubes.The partial replacement of inner-grooved aluminum tubes with inner-grooved copper tubes has important social and economic benefits.In order to better analyze the deformation law of the aluminum alloy tube during the internal thread spinning,design the process parameters,and obtain the aluminum tube that meets the requirements,the finite element simulation technology has become a better research approach.In this paper,the 5083 aluminum alloy as the test material,compression test under different deformation temperature and strain rate,analysis of the material at a temperature of 298-613K,the strain rate of 0.001?1170s-1 rheological behavior,the use of linear regression to obtain material With the dynamic constitutive model,the elastic-plastic finite element method was used to simulate and analyze the ball spinning process of 5083 aluminum alloy inner-grooved tube.The main conclusions are as follows:(1)At the temperature of 298K,when the strain rate of the 5083 aluminum alloy is slow(0.001?0.1s-1),It exhibits obvious strain hardening characteristics,and it is found that when the strain rate is relatively small,the material mainly exhibits the strain hardening effect.As the strain rate fster than 10s-1,the5083 aluminum alloy is rendered due to the adiabatic temperature rise.There is a certain strain softening effect.(2)Dynamic constitutive model of 5083 aluminum alloy based on friction and temperature rise correction has high accuracy,The relative error between flow stress and experimental values predicted by the J-C model is a maximum of 5%,It can better predict the variation of flow stress with deformation parameters under different deformation conditions.(3)The simulation results of inner-grooved ball spinning show that:during the spinning process,the major strain areas of the tube blank are mainly concentrated in the arc regions on both sides of the thread tooth groove;The speed of the motor and the drawing speed together affect the partially formed thread teeth and the subsequently filled metal flow to form a fold;The height of the thread tooth increases with the increase of the ball diameter,the diameter gets a certain range,the tooth height area is stable,while the increase of the rear ball diameter reduces the tooth height;The greater the feed ratio is,the more difficult it is to ensure the continuity of the thread teeth forming,and the smaller the feed ratio is.Although the tooth quality is guaranteed,the production efficiency is reduced.For aluminum tubes of ?7.54×0.6 specification,the process parameters are ball diameter 10mm,feed ratio lmm/r,motor rotation speed 20000?35000r/min,and drawing speed 20?35m/min.