Desktop Manufacturing of Plasma Sprayed Coating and Computational Estimation of Its Mechanical Properties

Plasma-sprayed coatings are obtained through experimental iterations of various spraying parameters. The material properties of such coatings are greatly influenced by the particle temperature, impact velocities, and substrate pre-heat temperature. These are critical parameters that yield a unique microstructure with distinctive splat morphology, inter-splat boundaries, and volume fraction of heterogeneous phases. Due to this, experimental optimization of such coatings is an exhaustive iterative process that leads to excessive time and resource utilization. Splat simulations for feedstock particles are obtained using a commercial computational fluid dynamics tool. These simulated splats are modeled stochastically to obtain a simulated 3-dimensional plasma sprayed bulk. The goal is to develop a methodology to simulate the computational microstructure of plasma sprayed Al2O3 and estimate the mechanical response of the coating using microstructure-based analysis. Object Oriented Finite element analysis (OOF2) is an image-based numerical analysis tool developed by the National Institute of Standards and Technology (NIST). It can account for actual microstructural characteristics and evaluate the thermal and mechanical properties of heterogeneous materials. Development of this “Desktop Manufacturing Protocol” for plasma sprayed coatings will reduce the number of experiments required to obtain the bulk and its microstructure of desired thermo-mechanical properties.