METHOD FOR DETERMINATION OF STRAIN STRENGTHENING CHARACTERISTICS OF CONSTRUCTIONAL TITANIUM ALLOY

摘要

The invention relates to non-ferrous metallurgy, in particular to a method for the determination of strain strengthening characteristics of constructional titanium alloy. The method includes operations of stretching standard smooth cylindrical specimen along one axis at different temperatures in interval from 4K to 293K, with determination of basic mechanical characteristics and characteristics of real breaking stress of the specimen Sand relative uniform contraction, plotting experimental dependence of plastic resistancein the region of uniform deformation, calculation of the value of intensity of breaking stress of the specimen, with plotting experimental dependences of plastic resistancein the region of non-uniform deformation characterized by keeping property of non-linearity or presence of break and increase of the angle of inclination of the dependence in interval of changes of strength on real strain at breaking point Sto the value of intensity of breaking stresses of the specimen, with determination of the group of alloy depending on the ratio of the values of strain strengthening characteristics at deformations lesser and larger compared to uniform one, with additional plotting experimental dependences, calculation of empirical coefficients on the basis of those and determination of strain strengthening characteristics by formulas:for the I-st group of alloys:,for the II-nd group of alloys:,wherein:- conventional fluidity limit, MPa,- real tension at breaking point, MPa,- breaking point, MPa,- real uniform deformation,- relative uniform contraction, in parts,- real deformation after destruction of the specimen,- relative contraction after destruction of the specimen, in parts,a = 82.23, b = 82.156, c = 0.041, d = 1.692 empirical coefficients.The invention provides increase of accuracy and self-descriptiveness of determination of strain strengthening characteristics of constructional titanium alloy within the region of non-uniform deformation by data of basic mechanical characteristics,,and the characteristic of relative non-uniform contractiononly, by those in complex capability of resistance t titanium alloy to transition to friable state is evaluated.