CAJ | 학술논문

金属粉末轧制工艺能够生产一般工艺难于或无法生产且成分精确、性能优良的板带材，是制取高性能以及特殊用途材料的粉末冶金成形工艺。在粉末轧制工艺的力学行为研究中，传统的数学模型被证明所提供的作用有限，基于有限元方法的数值模拟为此提供了一种灵活高效的途径。基于把粉末体看作是可压缩连续体的假设，根据椭球面屈服准则推导了金属粉末体变形的弹塑性本构关系。采用了合适的本构关系积分算法，并对摩擦模型进行了分析。基于MSC.Marc平台的二次开发工具编制了相关的用户子程序，对铁基粉末的轧制过程进行了三维弹塑性有限元数值模拟。该程序的准确性已在对粉末闭模压制的数值模拟及实验对比中得到了验证。此外，分析了轧制速度、摩擦系数等对轧制力和相对密度分布的影响。
금속분말알제공예능구생산일반공예난우혹무법생산차성분정학、성능우량적판대재，시제취고성능이급특수용도재료적분말야금성형공예。재분말알제공예적역학행위연구중，전통적수학모형피증명소제공적작용유한，기우유한원방법적수치모의위차제공료일충령활고효적도경。기우파분말체간작시가압축련속체적가설，근거타구면굴복준칙추도료금속분말체변형적탄소성본구관계。채용료합괄적본구관계적분산법，병대마찰모형진행료분석。기우MSC.Marc평태적이차개발공구편제료상관적용호자정서，대철기분말적알제과정진행료삼유탄소성유한원수치모의。해정서적준학성이재대분말폐모압제적수치모의급실험대비중득도료험증。차외，분석료알제속도、마찰계수등대알제력화상대밀도분포적영향。
In spite of its simplicity and low cost, the rolling compaction process can produce strips or plates with homogeneous and satisfactory mechanical properties. The mechanical behaviors of rolling compaction are difficult to predict accurately by traditional means. The Finite Element Method (FEM) provides an efficient approach for such problems. Based on the assumption that the powder system is a compressive continuous material, three-dimensional FEM simulations for the rolling compaction process of the iron matrix powder were proposed. The ellipsoidal yield criterion was analyzed. The correspondent elasto-plastic constitutive relationship was derived from the yield criterion. Appropriate integration algorithm and friction model were applied. The user subroutine was developed and three-dimensional simulations were performed in MSC.Marc. Effects of friction coefficient and rolling velocity of the rollers on the rolling force and the distribution of the relative density were analyzed.