Modeling Of Transverse Thickness Distribution And Determination Of Process Parameters Of Hot Rolling Finishing Pass Of Aluminum Strip

Abstract:Aluminum strip is a kind of versatile material of high-quality, high-precision and high-performance, which is widely used in many fields of national economy, such as aerospace, weapon, transportation and so on. The amount of its demand is more and more increasing and the manufactured accuracy is also required to improve increasingly. On the one hand, given this situation of thinner thickness and higher accuracy requirements for hot-rolled aluminum strip and further to use cold-rolled aluminum strip partly instead of hot-rolled one, it is necessary to solve a series of problems, such as to eliminate the factors that block production of thinner strip through hot-rolled process directly, to improve the forming limit of material and to bring the accuracy and performance of hot-rolled strip nearer to the cold-rolled. On the other hand, it is an urgent problem in current production that how to select reasonable process parameters of hot rolling, especially how to determine one of hot rolling finishing pass, according to the requirements of cold-rolled strip flatness.In this paper a transverse thickness distribution prediction model of hot rolling aluminum strip was built. According to the requirements of cold-rolled strip flatness, a method for determining hot rolling finishing pass process parameters was proposed. The specific contents are as follows:(1) The calculation formula of cold-rolled strip residual stress transverse distribution was built on the basis of analyzing flatness factors. The finite element software Marc was used to simulate cold rolling process, which validated the effectiveness of cold-rolled strip residual stress calculation formula.(2) The calculation formulas of hot rolling spread and exit transverse displacement was deduced. The relationship between residual stress and transverse thickness distribution of hot-rolled strip was established.(3) The relationship between shape defects and transverse thickness distribution was analyzed. Mapping between various shape defects, such as unilateral wave, center wave, bilateral wave, rib wave, etc., and transverse thickness distribution were built.(4) Influence function method and local one-dimensional implicit difference method were utilized to study transverse thickness distribution of hot-rolled strip. According to the requirements of cold-rolled strip flatness, a method for determining process parameters of hot rolling finishing pass was proposed.47figures,3tables,75references...