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

小行星9457205 该奖项是为研究集中在联盟的纳米相材料合成和净形成制造与控制熔融金属液滴沉积。 从毛细管流破裂产生液滴的新方法使得能够更高水平地控制和操纵液滴特性（例如， 液滴尺寸和分离）比用常规的液滴产生方法所能获得的要小。 液滴轨迹的精确控制（1微弧度量级的角分散）是净成形制造要求的基础。 液滴尺寸和轨迹的控制导致沉积液滴的固化特性的控制。 当液滴撞击到温度受控的基底上时，它们“飞溅”并迅速固化。 快速凝固导致具有精细微/纳米结构的材料的合成。 初步实验表明， 由低熔点铋锡合金组成的纳米相材料。 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，以及用于优化净成形制造和具有较高熔点材料的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成型或净成形制造的制造学科，为可能提高国家工业基础竞争力的新型高效制造工艺打开了大门。 研究的影响有三个方面。 首先，净成形制造具有显著的经济效益，因为工程部件是在一个集成操作中由原材料制成的，从而消除了许多加工步骤。 第二，已知非晶材料合成可产生具有增强的机械和磁性的材料。 第三，由于小颗粒的快速凝固，由于宏观偏析而不能通过常规方法制备的新合金的合成现在是可能的，这将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.