半固态合金强流变轧制单位轧制压力分布的数学模型和理论研究

来源期刊：金属学报2011年第3期

论文作者：黄红乾 曹富荣 管仁国 赵占勇 邢振环

文章页码：291 - 297

关键词：半固态； 流变轧制； 孔型轧制； 单位轧制压力； 数学模型； AZ91D

Key words：semisolid； rheo-rolling； groove rolling； unit rolling pressure； mathematical model； AZ91D

摘    要：建立了半固态合金强流变轧制过程封闭矩形孔型中单位轧制压力分布的数学模型,并以AZ91D镁合金为例,通过计算研究了轧制带材厚度、带材宽度和轧辊半径对单位轧制压力分布的影响规律.结果表明,强流变轧制带材的厚度越小,宽度越窄,单位轧制压力峰值越大,平均单位轧制压力也越大;随着带材厚度减小,单位轧制压力峰值向出口移动,而随着带材宽度减小,单位轧制压力峰值向入口移动;随着轧辊半径增大,单位轧制压力的峰值和平均轧制压力都增大,峰值逐渐向出口偏移.

Abstract: Semisolid metal forming (SSF) is recognized as a new forming technology,which has been paid more and more attention by the researchers all over the world.The semisolid rolling process (rheo-rolling) combines the fabrication of semisolid slurry with continuously rolling as an important neoteric means to achieve near-shape forming.Compared with the traditional rolling process,this technology has the features of short machining process,low energy consumption,low cost equipment and high yield.However,one of the difficulties of using this technology to produce strip is that the solid and liquid phases prone to separation with each other during rheo-rolling deformation,especially when the semisolid slurry has a low solid fraction.The phenomenon causes macrosegregation and reduces the quality of the strip,as a result,limiting its industrial application.Using rectangular groove roller may solve this problem.In this paper,the mathematical model of unit rolling pressure distribution in rectangular groove during rheo-rolling was established.AZ91D magnesium alloy was taken as an example,and the effects of rolling strip thickness,width and roller radius on unit pressure were calculated and studied.The calculation results reveal that the smaller the thickness of rheo-rolled strip is,the narrower the width is,the bigger the peak unit rolling pressure is and the larger the average unit rolling pressure is.However,when the strip thickness decreases,the peak unit rolling pressure moves towards the exit while when width decreases,the peak unit rolling pressure moves towards the entrance.The larger the roller radius is,the bigger the peak unit rolling pressure is,the larger the average unit rolling pressure is,and the peak value deviates towards the exit.