Microstructural Transformations of a Duplex Steel Weld and their Influence on the Particle and Cavitation Erosion Resistance

Original scientific paper The microstructural transformations which took place during the welding of duplex steel as well as their influence on the resistance to particle erosion wear and cavitation erosion wear were investigated. A sample was cut from a 1.4462 rolled steel plate and heat treated in order to obtain a microstructure which would resemble, as closely as possible, the actual welded microstructure. Qualitative and quantitative microstructural analyses were performed on the samples. The influence of the sigma phase and its volume fraction (obtained by annealing at 800 °C) was investigated, as well as the influence of the various ferrite/austenite ratios (obtained by annealing in the 1100 °C —1300 °C temperature range) on particle erosion and cavitation erosion resistance. It was found that the microstructural transformations which took place in the weld zone and the heat affected zone significantly influence resistance to wear in the investigated cases.