N. A. Minina

Experimental investigation of acoustic properties of titanium alloys in the temperature range of 20–1000°C

Titanium and titanium-based alloys, which are widely used in various sectors of the national economy, require deep and versatile investigations of their physico-mechanical properties in a wide temperature range. Numerous abnormal physical phenomena are observed in titanium-based alloys at high temperatures, especially in the region of polymorphic transformation. In particular, in addition to significant structural variations, which influence the strength properties of the final products, near such transformations the titanium alloys (especially with a fine structure) have a tendency to superplastic deformation, which is widely applied in modern technology. Among the physical characteristics, which provide extensive information about the structural and physico-mechanical properties of titanium alloys, are the temperature expansion and acoustic properties (in particular, the speed of ultrasound, information about the temperature dependence of which is unavailable for the majority of engineering materials), which allow the Young modulus for these materials to be calculated.

Experimental study of the Er308LSI steel acoustic properties

The experimental results on the acoustic properties (the ultrasound velocity and attenuation coefficient) and the relative thermal expansion of the Er308LSI steel within the temperature range of 20–1100°C are presented. Application of the dilatometer studies makes it possible to improve the accuracy of the experimental data on the acoustic properties and to calculate the temperature dependency of the steel density as well as of the Young modulus. The temperature dependencies and calculate the approximating equations for the investigated and the calculated properties of the steel are plotted.

Investigation of the acoustic properties of zirconium

The results of an experimental study of the acoustic properties (speed and attenuation factor of ultrasound), the acoustic-emission properties, and the relative temperature expansion of zirconium in a temperature range of 20–1000°C are presented. The least-squares method was used to obtain approximating equations for the temperature dependences of the studied and calculated thermophysical properties of zirconium.

Investigation of the acoustic properties of cobalt

The results of the experimental investigation of the acoustic (ultrasound velocity and attenuation coefficient) and acoustic-emission properties, as well as of the relative thermal expansion of cobalt, within the temperature range of 20–1100°C are presented. By the mean square method, we obtain the approximating equations for the temperature dependencies of the investigated and the calculated thermophysical cobalt properties.

An investigation of the kinetics of structure transformations and phase transition in nickel using acoustic methods

Results are given of experimental investigation of the temperature dependence of the acoustic and acoustic-emission properties of nickel in the vicinity of magnetic phase transition (Curie point), as well as of their behavior in the process of annealing and quenching. The information content of these properties is demonstrated when investigating the evolution of nonequilibrium structures and phase transitions of metal materials.

Experimental investigation of the acoustic properties and the microhardness of U8 steel

The acoustic properties (ultrasound velocity, attenuation coefficient) and the relative elongation of U8 steel are studied in the temperature range 20–1050°C and its microhardness is studied in the range 20‒500°C. The measured relative elongation can improve the accuracy of determining the ultrasound velocity and the attenuation coefficient and can be used to calculate the temperature dependences of the density and Young’s modulus of the steel. Approximating equations for the temperature dependences of the experimental and calculated mechanical and thermophysical properties of the steel are derived.

Experimental study of acoustic properties and microhardness of 09Mn2Si steel

We present experimental study results of the ultrasound velocity, the relative thermal expansion (within 20–1000°C) and the microhardness (within 20–500°C) of 09Mn2Si steel. From the experimental data, we calculate density and Young modulus values. We treated the hardened and the annealed specimens. The mean-square processing of the experimental results makes it possible to obtain the approximating equations of the temperature dependences of the studied and the calculated steel properties.

Investigation of acoustic properties of Russian grade 1Cr18Ni10Ti steel

This article presents results of experimental study of the acoustic properties (speed and coefficient of attenuation of ultrasound) and relative temperature expansion of Russian grade 1Cr18Ni10Ti steel in the temprature range of 20–1100°C. The approximating equations for temperature dependences between experimental and calculated thermophysical and mechanical properties of steel are obtained.

Acoustic properties of titanium nickelide

Results of the experimental investigation of the acoustic properties of titanium nickelide alloy (speed of ultrasound and ultrasonic attenuation factor) are presented. The approximating equations for the temperature dependences of experimental data on the speed of sound, relative temperature expansion, and the density and Young’s modulus values calculated on their basis are obtained.

The kinetics of structure transformations in martensitic structural steel

The behavior of the acoustic properties and acoustic-emission activity of 08Kh14AN4MDB (chrome-nitrogen-nickel-molybdenum-copper-niobium) structural steel is investigated in the process of annealing and after quenching. The significant information content of acoustic methods is demonstrated, especially that of the acoustic emission method, from the standpoint of investigating the kinetics of the processes occurring in materials of nonequilibrium structure.