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

本研究项目涉及金属基复合材料（MMCS）的实验、理论和工艺优化。实验程序包括固化预渗透的复合材料样品，并在一定范围的环境压力和冷却速率下表征产品。这个实验将提供缺陷形成所需的临界压力作为冷却速率函数的信息。一个平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。实验数据将用于验证理论模型。最后，这些发现将在计算框架中用于优化铸造操作，以实现最小的缩孔率。预计该奖项将为研究连续纤维增强复合材料、增强/基体界面特性、预成型温度、基体过热和氢含量对孔隙形成的影响提供额外的资金，并将实验技术扩展到用预渗透的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.