Numerical Simulation And Performance Prediction Of 6061 Aluminum Alloy Hot-top Semi-continuous Casting

In recent decades,with the fast development of aluminum industry,the aluminum products are widely used in many fields on account of its lightness,aesthetic and low corrosive property.Considering the practical problems encountered during production and the purpose of enhancing productivity and reducing rejection rate as well as getting 6061 aluminum alloy products of good performance and stability,this article study the melt purification during melting process of 6061 aluminum alloy,analyze the casting technology's impact on ingot-casting production process of aluminum by using finite element numerical simulation method,and demonstrate the result by introducing JMatPro's analysis about 6061 aluminum alloy phase diagram and combining with homogenization annealing experiment and tensile test.The study prove,according to the calculation of JMatPro software,that the four kind of6061 aluminum alloy which has different element content has varied effect on phase change,the solidus temperature will decrease with the increase of Mg and Si element content,but the material strength will enhance;the material strength will also enhance if add 0.1% more Mn element,but the effect is not obvious.The 6061 aluminum alloy can preserve heat six hours at545? temperature condition,with the second phase of the interior of the grain has better solid solution and the segregation can spread averagely by comparison.It can also preserve heat six hours at 570? temperature condition,with the second phase of the interior of the grain and the grain boundary has complete solid solution and spread averagely,homogenization efficiency fastest.From the tensile experiment,it can conclude that T6 of 6061 aluminum alloy get advancement in tensile strength and yield strength and slight improvement in elongation with the increasing of Mg and Si element content.The simulated result show,that as for the 6061 aluminum alloy circular ingot in model?178,the faster the casting speed is,the deeper the liquid cave and the stronger the thermal stress is.When the casting speed arrives to 70mm/min,the solidification will enter into hot hood which will leading to the failure of pulling ingot-casting.When the casting speed arrives to 110mm/min,the shell of the ingot-casting is lower than the graphite annulus which will leading to cold shut and aluminum leakage.The best casting process is casting speed arrives to 90 mm / min and casting temperature at 680 ?.As for the phenomenon that the shell position of the circular ingot-casting with ? 258 mm in diameter is lower than graphiteannulus,it is improved by reduce casting speed to increase graphite annulus height during casting practicing.Above study conclusion prove that the calculation of material phase diagram has instructive significance on heat treatment technology and the simulated calculation result can roughly predict the material property.As for the coupling calculation of temperature field and stress field conduct on hot top semi-continuous casting,the simulated result is basically same with the actual production status.It can conclude that different casting technological parameters' effect on ingot-casting can direct industrial practice in certain degree.