Hot isostatic pressing (HIP) of powder mixtures and composites: Packing, densification, and microstructural effects
Hot isostatic pressing (HIP) of powder mixtures and composites: Packing, densification, and microstructural effects
复制标题
粉末混合物和复合材料的热等静压 (HIP)：填充、致密化和微观结构效应
DOI：
--
复制
发表时间：
1993
期刊：
影响因子：
--
通讯作者：
P. Funkenbusch
中科院分区：
文献类型：
--
作者：
E. Li;P. Funkenbusch
分析了粉末混合物（含有不同尺寸的组分）和复合粉末的热等静压（HIP）。最近的进展，包括一个简单的计划估计径向分布函数的发展，这些系统的建模实际。在实验上，观察到含有双峰或连续尺寸分布的粉末在相同的加工条件下热等静压到更高的密度，并且当与通常假设用于建模目的的“单一尺寸”粉末相比时，显示出作为密度的函数的致密化速率的大差异。建模正确地预测这些趋势，并表明它们可以部分地，但不完全，归因于初始堆积密度的差异。建模还预测了混合物中较小颗粒的变形增加。这种效应也被实验观察到，并与微观结构的变化，如小颗粒的优先再结晶。最后，固结的复合混合物含有硬，但可变形，夹杂物已被建模与现有的实验数据进行比较。建模结果相匹配的致密化和微观结构的观察实验报告。致密化由于增强颗粒之间的接触而延迟，所述增强颗粒支撑所施加的压力的大部分。此外，软基体和硬夹杂物粉末之间的变形“分配”导致较软材料的变形增加。
Hot isostatic pressing (HIP) of powder mixtures (containing differently sized components) and of composite powders is analyzed. Recent progress, including development of a simple scheme for estimating radial distribution functions, has made modeling of these systems practical. Experimentally, powders containing bimodal or continuous size distributions are observed to hot isostatically press to a higher density under identical processing conditions and to show large differences in the densification rate as a function of density when compared with the “monosize” powders usually assumed for modeling purposes. Modeling correctly predicts these trends and suggests that they can be partially, but not entirely, attributed to initial packing density differences. Modeling also predicts increased deformation in the smaller particles within a mixture. This effect has also been observed experimentally and is associated with microstructural changes, such as preferential recrystallization of small particles. Finally, consolidation of a composite mixture containing hard, but deformable, inclusions has been modeled for comparison with existing experimental data. Modeling results match both the densification and microstructural observations reported experimentally. Densification is retarded due to contacts between the reinforcing particles which support a significant portion of the applied pressure. In addition, “partitioning” of deformation between soft matrix and hard inclusion powders results in increased deformation of the softer material.