Cold spray modeling: An analytical method for predicting bulk properties of cold spray deposits

In the drive towards improved electrical energy storage for applications ranging from electric vehicles to grid stabilization and renewable energy storage, the important role and great need of electrochemical storage and batteries specifically will continue, due to batteries’ high energy density, simplicity, reliability, and potential for favorable performance/cost ratio. A redox flow battery combines the advantages of conventional batteries and fuel cells, and can be designed for high power applications as well for high capacity electricity storage. However, they have low power density (~40mA/cm2) and energy density (~30Wh/L) because of the solubility limit of active materials in solution, which prevent them from being widely used. Here we propose to demonstrate a new type of flow battery with Ni/Zn chemistry in a state of suspension, which offers high power and energy densities. The success of the proposed research can provide a new solution for the energy storage with high energy density, high power density, high safety, low cost, and long cycle life. Cold spray modeling: An analytical method for predicting bulk properties of cold spray deposits Authors: Student: Luke Bassett Advisor: Richard D. Sisson, Jr. Abstract: Cold spray deposition is a rapidly growing material consolidation process in which ductile particles, typically metal, are accelerated by a high velocity gas stream and impinged onto a substrate with sufficient energy to induce bonding. The subsequent consolidated structure has very high strength and hardness when compared to a similar wrought alloy, and can be built up to any reasonable desired thickness. Predictive modeling has been carried out for various portions of the process; however there is currently no all-encompassing model that can calculate the final microstructure and bulk properties based on process parameters and material characteristics. The goal of this project is to develop a complete model that integrates existing models with new predictive calculations to fill in portions that are currently lacking or inadequate. The resulting model will be validated using experimental results. Cold spray deposition is a rapidly growing material consolidation process in which ductile particles, typically metal, are accelerated by a high velocity gas stream and impinged onto a substrate with sufficient energy to induce bonding. The subsequent consolidated structure has very high strength and hardness when compared to a similar wrought alloy, and can be built up to any reasonable desired thickness. Predictive modeling has been carried out for various portions of the process; however there is currently no all-encompassing model that can calculate the final microstructure and bulk properties based on process parameters and material characteristics. The goal of this project is to develop a complete model that integrates existing models with new predictive calculations to fill in portions that are currently lacking or inadequate. The resulting model will be validated using experimental results. Process Control Modeling for Laser Assisted Cold Spray: A Novel Deposition Technique Authors: Student: Aaron Birt Advisor: Richard D. Sisson, Jr. Abstract: Cold spray is a deposition process whereby particles are accelerated via a high temperature and pressure gas through a DeLaval nozzle to supersonic speeds. The particle then impacts a substrate and adheres due to extreme localized conditions. These particles can range from metals and cermets, to polymers and composites, and can be deposited to generate either a coating or a free-standing structure. The cold spray process has many applications including corrosion repair, antimicrobial Cold spray is a deposition process whereby particles are accelerated via a high temperature and pressure gas through a DeLaval nozzle to supersonic speeds. The particle then impacts a substrate and adheres due to extreme localized conditions. These particles can range from metals and cermets, to polymers and composites, and can be deposited to generate either a coating or a free-standing structure. The cold spray process has many applications including corrosion repair, antimicrobial surfaces, structural repair of damaged systems, and additive manufacturing. However, cold spray has only recently become a mainstream process thus there are gaps in the knowledge bases for many applications. This thesis will focus on increasing the ability of the end user to control the deposition process by developing a series of models to control parameters such as particle velocity, temperature , and composition so that rather than estimating the parameters needed to achieve a desired quality the user may consciously choose the parameters. In order to have an added measure of control over the conditions of the substrate and particles, a high-powered laser will be attached directly to the cold spray nozzle so that the laser can preheat the substrate, ablate the existing oxide layer, or preheat the particles depending on the its exact orientation. The development of numerical and experimental models for the Laser Assisted Cold Spray process will enable the user to match the precise parameters needed to generate a deposit of the quality and size desired. Friction Stir Processing in Wrought and Cast