VM12 steel for advanced power generation plants - metrology of the precipitates by electron microscopy

摘要

A new high chromium martensitic steel, VM12, has been recently developed for advanced coal-fired ultra-supercritical steam power plants. A very important factor in maintaining high creep resistance during service exposure is its stable microstructure, in particular high dispersion particle strengthening, which slows down the recovery and softening processes of the matrix. Quantitative characterisation of the precipitates in the VM12 steel as received condition and after creep tests up to about 30000 h at 625°C using TEM was carried out.