A Study on the Causes of the Destruction of the Heat-resistant Steel of the Furnace and Development of a Method of Protection

Issue 1(83) 2017
Pages 39-44

A.B. Laptev, Federal state unitary enterprise «all-Russian research Institute of aviation materials», Moscow
E.V. Nikolaev, Federal state unitary enterprise «all-Russian research Institute of aviation materials», Moscow
M.R. Pavlov, Federal state unitary enterprise «all-Russian research Institute of aviation materials», Moscow


Keywords: heat-resistant steel, alkaline cracking, pyrolysis, x-ray structure analysis, the amine neutralizer

The chemical composition of the steel was determined by the methods of energy dispersive spectroscopy. Phase composition of steels was determined by X-ray structure analysis. Processing of experimental data was performed using Rietveld method.
It was established that the cause of the destruction of heat-resistant HTR steel is the change the structure on the inner wall of the chimney due to the dissolution and substitution of the iron by sodium ions, the development of alkaline cracks which is aggravated by formation of carbon deposits in the dissolution areas resulting in local overheating of the wall and the intensification of crack growth.
A method of preventing the alkaline cracking of heat-resistant steel by reducing the concentration of the sodium hydroxide was proposed by additional dosing of the neutralizer.