镁合金板材颗粒介质拉深工艺参数数值模拟  

Numerical simulation on granules medium drawing process parameters of magnesium alloy sheet

作　　者：曹秒艳[1] 赵长财[1] 董国疆[2] 

机构地区：[1]燕山大学机械工程学院,秦皇岛066004 [2]燕山大学车辆与能源学院,秦皇岛066004

出　　处：《中国有色金属学报》2012年第11期2992-2999,共8页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(50775197);秦皇岛市科技支撑计划资助项目(2012021A094)

摘　　要：为提高镁合金板材拉深性能,提出一种基于固体颗粒介质成形（Solid granules medium forming,SGMF）工艺的镁合金板材差温拉深工艺。以单向拉伸试验获取的AZ31B镁合金板材真应力—应变曲线和颗粒材料性能试验构建的介质线性Drucker-Prager本构模型为基础,采用有限元法对板材拉深成形进行热力耦合数值模拟并进行试验验证,研究压边力、压边间隙和温度对板材拉深性能的影响。结果表明：压边间隙和压边力联合控制比单纯控制压边力或是压边间隙更能有效地提高板材拉深性能;AZ31B镁合金板材在拉深过程中对温度有较强敏感性,板材变形温度为250~300℃,颗粒介质与其温差100~150℃时,板材达到最佳拉深性能;颗粒介质能够对工件筒壁部位提供轴向摩擦力,该摩擦力能有效提高材料拉深性能并保证板厚的均匀性,这是SGMF工艺的优势所在。In order to improve the deep drawing performance of magnesium alloy sheet,the non-isothermal drawing technology of magnesium alloy sheet based on solid granules medium forming（SGMF） was proposed.Based on the true stress—strain curves of AZ31B magnesium alloy from uniaxial tensile tests and the Drucker-Prager constitutive model with granular material performance tests,the thermo-mechanical couple numerical simulation of magnesium alloy sheet deep drawing with finite element method was performed,and the deep drawing tests were also carried out in order to validate the numerical model.The influences of process parameters,such as blank holder force,blank holder gap and temperature,on the deep drawing performance of AZ31B magnesium alloy sheet were investigated.The results show that the combination controlling the blank-holder gap and blank holder force can improve the deep drawing performance of sheets more effectively than simply controlling only one of them.The AZ31B magnesium alloy sheet is sensitive to the temperature in the process of deep drawing,under the conditions of the forming temperature from 250 ℃ to 300 ℃ and the temperature difference from 100 ℃ to 150 ℃ to solid granules medium,the sheets achieve the best deep drawing performance.The granules medium can put axial friction on the cylinder wall and the force can improve the deep drawing performance of sheets and ensure their thickness evenness.

关 键 词：AZ31B镁合金 固体颗粒介质成形 差温 数值模拟 

分 类 号：TG146.2[一般工业技术—材料科学与工程]