GOALI: Shrinkage Porosity and Optimization of Metal-Matrix Composite Processing

本研究计画包括金属基复合材料之实验、理论及制程最佳化。 实验程序包括固化复合材料的预渗透样品，并在一系列环境压力和冷却速率下表征产品。该实验将提供关于作为冷却速率的函数的缺陷形成所需的临界压力的信息。 一个并行的理论程序将进行数值预测凝固模式和孔隙率分布在这些工艺条件下。 实验数据将被用来验证理论模型。 最后，这些研究结果将被利用在一个计算框架，以优化铸造操作最小的收缩孔隙。 预计该奖项将提供杠杆作用，以获得额外的资金来研究连续纤维增强复合材料，增强/基体界面特性的影响，预制件温度，基体的孔隙度和氢含量对孔隙形成，并将实验技术扩展到从预渗透小部件制造大型铸件。

This research project involves experimental, theoretical and process optimization for the metal-matrix composites (MMCS). The experimental program involves solidifying pre-infiltrated samples of the composite and characterizing the product under a range of ambient pressure and cooling rates. This experiment will provide information on the critical pressure required for defect formation as a function of the cooling rate. A parallel theoretical program will be undertaken to numerically predict solidification pattern and porosity distribution under these process conditions. The experimental data will be used to validate the theoretical model. Finally, these findings will be utilized in a computational framework to optimize the casting operation for minimal shrinkage porosity. It is anticipated that this award will provide leveraging to obtain additional funds to study continuous-fiber-reinforced composites, the influence of reinforcement/matrix interfacial characteristics, preform temperature, matrix superheat and hydrogen content on porosity formation, and extension of experimental technique to the fabrication of large castings from pre-infiltrated small components.