The Internal Attack of 20%Cr/25%Ni/Nb Stainless Steel Revealed by Selective Etching

Improved procedures have been developed, by combining mechanical abrasion with selective etching, for the preparation of specimens to enable specific aspects of the attack of alloys to be examined more extensively by conventional surface analytical techniques, such as scanning electron microscopy and X-ray diffraction. The techniques have been utilised for the microstructural characterisation of the internal attack of 20Cr/25Ni/Nb stainless steel in CO₂-based environments at 900–1000°C.