Abstract: A turbine blade designing method is for designing a turbine blade formed using a metal material in which creep including diffusion creep and dislocation creep occurs by heating. The turbine blade designing method includes: acquiring temperature distribution data relating to temperature distribution in the turbine blade to be heated; acquiring creep strength distribution data relating to distribution of the creep strength required for the turbine blade to be heated; from the correlation data, based on the temperature distribution data and the creep strength distribution data, setting the crystal grain size of a high-temperature portion that is the diffusion creep temperature range of the turbine blade to a size coarser than the reference crystal grain size, and setting the crystal grain size of a low-temperature portion that is the dislocation creep temperature range of the turbine blade to a size finer than the reference crystal grain size.

Abstract: A turbine blade designing method is for designing a turbine blade formed using a metal material in which creep including diffusion creep and dislocation creep occurs by heating. The turbine blade designing method includes: acquiring temperature distribution data relating to temperature distribution in the turbine blade to be heated; acquiring creep strength distribution data relating to distribution of the creep strength required for the turbine blade to be heated; from the correlation data, based on the temperature distribution data and the creep strength distribution data, setting the crystal grain size of a high-temperature portion that is the diffusion creep temperature range of the turbine blade to a size coarser than the reference crystal grain size, and setting the crystal grain size of a low-temperature portion that is the dislocation creep temperature range of the turbine blade to a size finer than the reference crystal grain size.

Abstract: The precision of crack-propagation prediction is improved by taking into consideration a variation in the error due to inspectors and inspection methods. There is provided a crack-propagation prediction method including a correlation-information preparing step of measuring the length of a crack initiated in a test object by a plurality of inspectors and/or a plurality of inspection methods and obtaining correlation information between data acquired through the measurement and the condition of an actual crack; a crack-length estimating step of estimating the actual length of the crack initiated in an inspection target on the basis of the crack length measured by an inspector during inspection of the inspection target and the correlation information; and a crack-propagation-curve estimating step of estimating a crack-propagation curve of the inspection target originating from the crack length estimated in the crack-length estimating step.

Abstract: The precision of crack-propagation prediction is improved by taking into consideration a variation in the error due to inspectors and inspection methods. There is provided a crack-propagation prediction method including a correlation-information preparing step of measuring the length of a crack initiated in a test object by a plurality of inspectors and/or a plurality of inspection methods and obtaining correlation information between data acquired through the measurement and the condition of an actual crack; a crack-length estimating step of estimating the actual length of the crack initiated in an inspection target on the basis of the crack length measured by an inspector during inspection of the inspection target and the correlation information; and a crack-propagation-curve estimating step of estimating a crack-propagation curve of the inspection target originating from the crack length estimated in the crack-length estimating step.