NSF Young Investigator: Advanced Materials Synthesis and Manufacturing Techniques Using Controlled Droplet Deposition

9457205该奖项是为了表彰专注于纳米材料合成和网络制造与受控熔滴沉积相结合的研究。与传统的液滴生成方法相比，通过毛细管流分解生成液滴的新方法能够更高水平地控制和操纵液滴特性(例如，液滴大小和分离)。对液滴轨迹的精确控制(1微弧度量级的角度分散)是网络制造索赔的基础。对液滴大小和轨迹的控制导致对沉积液滴的凝固特性的控制。当液滴撞击到温度控制的衬底上时，它们会“飞溅”并迅速凝固。快速凝固导致合成出具有细化的微/纳米结构的材料。初步实验证明合成了由低熔点铋锡合金组成的纳米相材料。需要研究的技术问题包括传热和相变、液滴撞击的流体动力学以及优化网状制造和高熔点材料纳米材料合成的控制参数的表征。将液滴生成和控制方面的新研究应用于快速原型制造或网络制造的制造学科，打开了一种新的高效制造工艺的大门，这可能会提高国家工业基础的竞争力。这项研究的影响有三个方面。首先，网络成形制造具有显著的经济效益，因为工程零件是在一次集成操作中由原材料制成的，从而省去了许多加工步骤。其次，众所周知，非晶态材料合成可以产生具有增强的机械和磁性的材料。第三，由于DR晶团的快速凝固，由于宏观偏析而不能用传统方法合成的新合金现在有可能对工业和社会产生重大影响。

9457205 Orme The award is for research focused on the union of nanophase materials synthesis and net-form manufacturing with controlled molten metal droplet deposition. Novel methods of droplet generation form capillary stream break-up enable higher levels of control and manipulation of the droplet characteristics (e.g., droplet sizes and separations) than could be obtained with conventional methods of droplet generation. Precise control of the droplets trajectories (angular dispersion of the order of 1 micro- radian) is the basis for the net-form manufacturing claims. Control of the droplet sizes and trajectories leads to control of the solidification characteristics of the deposited droplets. As the droplets impinge onto a temperature controlled substrate, they "splat" and rapidly solidify. Rapid solidification leads to the synthesis of materials with refined micro/nano-structures. Preliminary experiments have demonstrated the synthesis of nanophase materials composed of low-melting point bismuthtin alloys. Technical issues to be investigated include heat transfer and phase change, fluid dynamics of droplet impact, and characterization of control parameters for optimization of net-form manufacturing and nanophase materials synthesis with higher melting-point materials. Application of novel research in droplet generation and control to the manufacturing discipline of rapid prototyping or net-form manufacturing opens the door to a novel and efficient manufacturing process that could likely increase the competitiveness of the nation's industrial base. The impact of the research is three-fold. Fist, net-form manufacturing has significant economic benefits since the engineering part is made from the raw stock in one integrated operation, thereby eliminating many machining steps. Second, noncrystalline materials synthesis is known to produce materials with enhanced mechanical and magnetic properties. Third, due to rapid solidification of the dr oplets, the synthesis of new alloys which could not be made by conventional methods due to macroscopic segregation is now a likely possibility which would have significant impact on industry and society.