In the Samara Polytech, the quality of metal is determined by the «sound»

08 Jul 2019

Sound impulses are captured with a unique installation

Acoustic emission unit is designed for continuous monitoring of the grain size of aluminum for foundries. The invention will help prevent production defects and simplify the production of alloys with high technological properties.

The acoustic analytical emission complex, developed by an interdisciplinary project team of scientists from the Samara Polytechnic, will provide timely information on the structure of the aluminum billet, and in case of a violation of the technological process - make adjustments.

The technological properties of the metal depend on the size of the grains that make up the metal structure: the smaller the grain, the more pliable and deformable the material is. Generaly, at modern metallurgical enterprises the testing of finished products takes several hours (preparation of a templet and its mechanical treatment, chemical etching, determination of the average grain size from the analyzed surface). If the structure of the alloy does not meet the requirements of the regulatory documentation, the cast product is rejected.

With the help of an acoustic emission installation, scientists at a Flagship University can predict the formation of a structure during the casting of ingots, as well as the formation of cracks, slag inclusions and porosity. Scientists recognize the deviations in the casting process from the required parameters by the sound vibrations that occur during the formation of the cast metal structure during crystallization.

«The signals may be different. It all depends on the rate of formation of grains, their size and morphology, – explains graduate student of the Institute of Automation and Information Technologies of the Samara Polytech Pavel Zobnin . – Our task is to fix these signals, analyze and build a mathematical model of the dependence of a pulse on changes in the metal structure. Right now we are working with aluminum, but we will experiment with other metals and alloys based on them».

The principle of operation of the Polytech’s complex is based on the registration and analysis of the nature of the passage of acoustic waves in an elastic medium, which is an aluminum melt. From there, as a voltage, signals arrive at the controller. The resulting digital code contains information about the structure of the metal. This code is decrypted by the software developed at the Samara Polytech.

«The prototype of the installation was developed in conjunction with the center of foundry technologies of the reference university using electronic measuring equipment from lcard. Today, the prototype is in the process of debugging and further testing at the metallurgical production. We already have agreements on the implementation of the system in Samara enterprises», – says Ekaterina Yaroslavkina , Project Manager, Head of the Information Measuring Technique Department at the Samara Polytechnic Institute.

According to scientists, their development is particularly relevant for the defense, aviation and automotive industries.

For reference:

Acoustic emission is a process of emission of elastic waves as a result of restructuring of internal structure of solids.

Samara Polytech is a Flagship university, a powerful research and educational center and a leader in the preparation of elite engineering personnel. Scientists guide research and development in almost all strategic sectors: Petrochemistry, Oil and Gas Production and Processing, Energy, Information, Pharmaceutical and Food Technologies, Construction and Architecture. In addition, the university actively participates in the State Armament Program, in solving strategic problems of the region and implementing significant projects of federal significance. University graduates are famous Russian scientists, government officials, leaders of leading companies.