论文部分内容阅读
采用离散体的有限元法对压制过程中的粉末颗粒进行了三维细观数值模拟,通过分析三维球形颗粒模型的位移和应变来研究粉末压制过程,进而考察了不同压制力下颗粒的应变情况以及不同模壁摩擦和压制压力下模坯密度的变化情况。结果表明,压制过程中粉末颗粒的变形主要有3个阶段:小变形的初级阶段、应变剧烈的主变形阶段和应变趋于稳定的最后阶段。压制压力的提高并不能无限地提高压坯密度,应根据不同的粉末特性选择适当的压制力。另外,选择合适的模具摩擦条件能有效地提高粉末冶金压制的生产效率和质量。
The three-dimensional numerical simulation of the powder particles in the compaction process was carried out by using the discrete finite element method. The powder pressing process was studied by analyzing the displacement and strain of the three-dimensional spherical particle model. Then the strain of the particles under different pressing forces was investigated. Different mold wall friction and pressing pressure under the blank density changes. The results show that there are mainly three stages of deformation of the powder particles during the pressing process: the primary stage of small deformation, the main deformation stage of severe strain and the final stage of strain becoming stable. The increase of pressing pressure does not increase the density of green compact indefinitely. Appropriate pressing force should be selected according to different powder characteristics. In addition, the selection of suitable mold friction conditions can effectively improve the production efficiency and quality of powder metallurgy pressing.