Effects of High-Temperature Exposure on Mechanical Properties of Thermal Sprayed CoNiCrAlY Alloy Coating

Thermal spraying is widely used in various industrial fields as effective surface modification method. In this study, mechanical properties of thermal sprayed CoNiCrAlY alloy coating were investigated. The coatings were prepared by three kinds of thermal spray methods. High-temperature exposure of the coated specimens was carried out in the atmosphere. After high-temperature exposure, apparent Young's modulus, strain tolerance, residual stress and hardness of the CoNiCrAlY coating were measured. These tests were also carried out using specimens without high-temperature exposure. As a result, the changes of mechanical properties caused by high-temperature exposure seemed to be correlated with properties of boundary between sprayed particles. From the results, effects of high-temperature exposure on mechanical properties of thermal sprayed CoNiCrAlY alloy coating were discussed.