A finite element modeling of the low pressure plasma deposition process—II: Stress analysis

Abstract

Thermal stresses that develop during the low pressure plasma deposition process and the subsequent temperature cycling period for a multi-layered composite material were analyzed using a finite element analysis method. Starting from the known temperature distribution in the deposit and substrate (Part I), the multi-layered material was cooled to room temperature, the steel substrate removed, was given an annealing heat treatment, and finally was exposed to a service environment. Computed thermal stresses and distortions that develop in the multi-layered composite showed marked effects of thermal and mechanical properties of each material. It was shown that the peak thermal stress could be reduced by the substrate removal process at low temperature, and maximum tensile and compressive radial stresses develop in the middle of each layer, not at the interface of adjacent materials. In addition, effects of temperature gradient heating and cooling on the thermal stress distribution were established. Such a computational pocedure may become a useful tool for the multi-layered composite alloy design and development.