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A molten metal droplet landing and bonding to a solid substrate is investigated with combined analytical, numerical, and experimental techniques. This research supports a novel, thermal spray shape deposition process, referred to as microcasting, capable of rapidly manufacturing near netshape, steel objects. Metallurgical bonding between the impacting droplet and the previous deposition layer improves the strength and material property continuity between the layers, producing high-quality metal objects. A thorough understanding of the interface heat transfer process is needed to optimize the microcast object properties by minimizing the impacting droplet temperature necessary for superficial substrate remelting, while controlling substrate and deposit material cooling rates, remelt depths, and residual thermal stresses. A mixed Lagrangian–Eulerian numerical model is developed to calculate substrate remelting and temperature histories for investigating the required deposition temperatures and the effect of operating conditions on remelting. Experimental and analytical approaches are used to determine initial conditions for the numerical simulations, to verify the numerical accuracy, and to identify the resultant microstructures. Numerical results indicate that droplet to substrate conduction is the dominant heat transfer mode during remelting and solidification. Furthermore, a highly time-dependent heat transfer coefficient at the droplet/substrate interface necessitates a combined numerical model of the droplet and substrate for accurate predictions of the substrate remelting. The remelting depth and cooling rate numerical results are also verified by optical metallography, and compare well with both the analytical solution for the initial deposition period and the temperature measurements during droplet solidification.

The Mechanical Engineering (ME) faculty at Western Kentucky University (WKU) have developed and implemented a Professional Plan to assure that graduates of the program will have experienced key areas of the engineering profession and demonstrated their abilities to perform in a professional manner. This Professional Component has been divided into Engineering Design, Professional Communications, Computer Skills Tools, and Engineering Ethics, with students receiving instruction and practice in each area at least once per academic year.Engineering Design experiences combine a structured approach to solving problems with an appreciation for the art of engineering. Professional Communications and Computer Skills Tools are introduced and then required throughout the four-year sequence to support the execution of design projects. The Engineering Ethics component provides students with a framework for understanding professional expectations and techniques for clarifying the ambiguity that is common in ethical dilemmas.The primary purpose of the Professional Component course sequence is to link all these skills to engineering design and to assess the progress of student capabilities through the curriculum. The integrated structure of the Professional Component courses provides a framework for building upon previous coursework, assessing student progress often, and more quickly adjusting course coverage based on prior assessments to effectively assure that graduates of the program are capable of practicing as engineers upon graduation.

The Mechanical Engineering faculty at Western Kentucky University have developed and implemented a Design of Experiments Plan to assure that graduates of the program have acquired the skills necessary to design and conduct experiments and analyze experimental results. The ME faculty have defined the components of design of experiments, agreed to levels of competence that are expected as a student progresses through the program, and developed assessment tools to quantify student achievement. Instruction is integrated over a dozen courses, and students finally demonstrate the ability to select experimental tools and methods, and apply them to analyze less-defined experimental problems in a senior capstone experimentation class. This class requires student teams to complete three different experiences—mechanical, materials and thermal. The Design of Experiments Plan provides a framework for building upon previous lab work, assessing student progress, and adjusting lab coverage based on prior assessments to assure that graduates of the program are capable experimental practitioners upon graduation.

Schmaltz teaches thermo-fluid and professional component courses in Mechanical Engineering, including the Freshman Experience course, Sophomore Design, Junior Design and the Senior Project Design course sequence. Prior to teaching at WKU, he was a project engineer for Shell Oil, designing and building oil and gas production facilities for offshore platforms in the Gulf of Mexico.