Contemporary nickel-base heat resistant alloys usually have a complex chemical composition, since they are required to satisf3' mapo', and sometimes conflicting, demands. In order to develop new compositions and predict their working properties computer techniques are widely used. This article is concerned with the methods of predicting the properties of heat resistant-nickel alloys using a computer.Earlier work on the use of computers in the metallurgy of gas turbine alloys was concerned with the prediction of phase stability [1][2][3], methods for evaluating the composition and amount of "y-, "7'-and secondary phases [4][5][6], calculation of the thermophysical properties [7], and development of heat-resistant alloys by statistical methods [8]. In the middle of the 1970s complex methods of predicting the structure and properties, applicable to the machine development of heat resistant alloy compositions considering many and varied requirements, depending on the use conditions and methods of manufacturing the components, became popular [9][10][11][12][13][14][15][16][17][18][19]. Simultaneously, directions for improving the methods of calculating the structural properties and phase composition of nickel-base alloys were evolved, which used more complete and exact models [20][21][22][23][24][25]. The studies carried out permitted the development of new wrought and cast alloys with equiaxed PC, columnar CC, and monocrystalline MC structures for blades and vanes, and also other parts of the hot section of mobile and stationary gas turbines.In Russia, the development of methods for predicting the structure, phase composition, properties, and machineplanning of heat-resistant nickel alloys also began in the middle of the 1970s [27][28][29][30][31][32][33].The present article gives a short description of the prediction methods developed by the author. As an example, the calculated characteristics and properties of the production alloy GTD111 (14% Cr, 9.5% Co, 3.8% W, 1.5% Mo, 2.8% Ta, 4.9% Ti, 3.0% AI, 0.05% Zr, 0.01% C, 0.01% B) with an equiaxed structure and the prospective alloy SC16 (16% Cr, 3% Mo, 3.5% Ta, 3.5% Ti, 3.5% A1) with a microcrystalline structure, designated for the production of turbine blades for a stationary installation is presented.The calculation scheme for predicting the structure, phase composition, and service properties is given in Fig. 1. The notations for the calculated properties, and the accuracy and prediction methods are given in Table 1. The factors considered include evaluation of the structure and phase composition through the cross-section of a dendritic cell; calculation of the temperature dependence of the properties, composition, and amount of the components, and also of the factors /Xa/a, AE/E, and AG/G up to 1000°C or the solidus temperature ts; use of new criteria for phase stability z, N~, e, P0; calculation of the directional dependence of the yield point and elastic properties.The method was based on the author's own and literature data and the application of various physic...
