A study on the Effects of Geometrical Parameters of Overlay Coated Layer on the Thermal Stress-strain Distributions of Co-based Super-alloy Deposited Layer on Hot-working Tool Steel

Chosun University in Gwang-Ju City, Korea

Abstract

Interests in an overlay coating technology, so called hardfacing technology, have steadily increased to improve the service life of hot-working tools through the reduction of the wear of tool surfaces. Characteristics of the overlay coated layer are dependent on geometrical parameters and material properties of sub-layers. The aims of the paper is to examine the effects of geometrical parameters of the overlay coated layer on thermal stress-strain distributions of Co-based super-alloy deposited layer on hot-working tool steel using finite element analysis (FEA). The overlay coated layer is designed as two sub-layers including the wear resistance layer with Co-based super-alloy and the thermal stress control layer (TSCL). The material of the TSCL is composed of 50 % of Co-based super-alloy and 50 % of hot-working tool steel. The protruded height and the inclined angle are chosen as geometrical parameters. The influence of the protruded height and the inclined angle on thermal stress-strain distributions in the vicinity of the overlay coated layer and the strain deviation in joined regions is quantitatively investigated. From the results of the investigation, an appropriate design methodology of the overlay coated layer is discussed.