FIELD: technical physics; metallurgy. SUBSTANCE: method is proposed for determining the microheterogeneity of a melt of a sample of a multicomponent metal alloy by obtaining the temperature dependences of the kinematic viscosity νi(Ti) during heating and cooling of the molten sample of this alloy in a certain temperature range, obtaining discrete values of the parameters νi(Ti) in form of electrical signals Ui. According to the claimed method, the value of the threshold of the second derivative d2(Ui)thr is set, the transformations associated with the change in the microheterogeneous state, with the change in the activation energy EA of the viscous flow, are determined. Graphs ln(νi) of the reciprocal temperature 1/T in form ln(νi)=ϕ(1/Ti) are charted. Data in form of electrical signals Ui~ln(νi) is differentiated twice to get d2(Ui). It is compared with threshold d2(Ui)thr: if value d2(Ui) is less than d2(Ui)thr, then the anomaly in the dependence νi(Ti) is considered to be absent, and when d2(Ui) is greater than the threshold signal d2(Ui)thr, there is an anomaly, which allows to conclude that there is a structural transformation in the melt. A synchronous graph is built for magnitude Ui~ln(νi)=ϕ(1/Ti), that is approximated by straight lines reflecting the course of ln(νi)=ϕ(1/Ti) before and after the anomaly. Value of the slope of these lines in form of angles α1 and α2 is determined. In the absence of an anomaly, these angles are equal; in presence of an anomaly, angle α1 is more than angle α2, and the presence of an anomaly is accompanied by a decrease in the activation energy EA1 of the viscous flow of an inhomogeneous melt, which is proportional to tg α1, up to the value of EA2 proportional to tg α2. After that, a conclusion is made about transition of the tested melt into a more homogeneous state when it is heated above the temperature of the anomaly Ti=Tan. EFFECT: reduced wear of equipment, clarity and reliability of determining the temperature anomaly of the sample, even in the absence of hysteresis for dependencies νi(Ti), which makes it possible to determine the temperature of anomaly Tan using the temperature dependence νi(Ti) obtained only during the sample heating mode. 1 cl, 4 dwg.
Translated title of the contributionMethod for Determining Microheterogeneity of a Melt of a Sample of a Multicomponent Metal Alloy: patent of invention
Original languageRussian
Patent number2795262
IPCG01N 11/00,G01N 27/14,G01N 25/02
Priority date01/09/2022
Filing date01/09/2022
Publication statusPublished - 2 May 2023

ID: 47015560