Effect of calcium sulfate particles on corrosion and erosion-corrosion of carbon steel

In laboratory erosion-corrosion and corrosion experiments it was determined that calcium sulfate which occurs in fluidized bed combustion materials from the reaction of calcined limestone with the sulfur in the coal fuel can either protect the base metal against erosion-corrosion by aiding the formation of mixed calcium-compound-iron-oxide layers on the surface or promote its sulfidation, depending on the calcium sulfate content of the erodent particles and the test temperature, particle velocity, and duration. The reaction between calcium sulfate particles and metal substrates produced iron sulfide under certain test conditions.