METHOD OF FORECASTING DEGREE OF HEAT-RESISTANT STEEL EMBRITTLEMENT Russian patent published in 2014 - IPC G01N3/28 G01N33/20 C21D1/26 

FIELD: instrumentation.

SUBSTANCE: preliminary, levels of grain-boundary phosphorus segregation in check test pieces made from steels of analysed reactor body subjected to long-term temperature effects. Accumulation of segregation at reactor operation termination is defined by extrapolation. Then, pilot specimens of steel with composition and microstructure approximating to those of reactor material are made. Said specimens are subjected to embrittlement annealing at maximum temperature of development of temper brittleness during different time intervals. Brittleness critical temperature shift (Tcr) and segregation level of specimens subjected to annealing is defined. Correlation between said shift and segregation level is defined. Obtained correlation curve and extrapolation of segregation accumulation level are used to define embrittlement degree in planed term of reactor operation.

EFFECT: longer life of reactors.

2 dwg