Girish Gupta

Effect of Lvof Spray Method in Oxidation and Hot Corrosion Girish Gupta

High temperature oxidation & hot corrosion causes degradation of materials in power plant boilers and gas turbines . To obviate this problem oxidation & hot corrosion behaviour of Boiler Steel SA-192 and Cobalt based superalloy of coated & uncoated has been studied in air & Na2SO4+60%V2O5 at 850C & 950C. For determining the effect of LVOF spray method we have coated both specimen . Coating has been done by LVOF of Al2O3+40%TiO2 . At both temperature superalloy go through cyclic oxidation which consist of 1 hrs heating in Kanthol wire tube furnace followed by 20 minutes cooling in ambient air. Weight change has been taken after each cycle by digital electronic balance machine which has accuracy of 1 mg. Results come in form of weight change , we divide it by total surface area of used specimen and plot a graph between weight gain and Number of cycle. Results shows Coating reduces the oxidation and hot corrosion rate in all types of environment for both materials .