A NEW AUSTENITIC ALLOY CONTAINING 3.5-PERCENT VANADIUM RESISTANT TO COAL GASIFIER CORROSION ENVIRONMENT

A new alloy containing 26.5% Cr, 39% Ni, 3.5% V, 0.3% Nb and 0.02% N w as developed for heat exchangers of coal gasification power plants. Th is alloy is expected temperature sulfidation and aqueous corrosion dur ing down time. Laboratory-melted alloys of various compositions were p repared to optimize the alloy composition with respect to mechanical p roperties. The Greeble test, tensile test, creep rupture test. Charpy impact test for aged materials, and the Trans-Varestraint test were pe rformed. Changes in the microstructure of the alloys upon ageing were investigated by optical and electron microscopy, along with chemical a nalyses of the precipitates.