Wyniki wyszukiwania - BazTech

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Determination of thermal diffusivity values based on the inverse problem of heat conduction - numerical analysis

Adamowicz Adam

Acta Mechanica et Automatica

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2022

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Vol. 16, no. 4

399--407

EN

This paper presents a discussion on the accuracy of the method of determining the thermal diffusivity of solids using the solution of the inverse heat conduction equation. A new measurement data processing procedure was proposed to improve the effectiveness of the method. Using the numerical model, an analysis of the sensitivity of the method of thermal diffusivity determination to changes in operational and environmental parameters of the test was carried out. The obtained results showed that the method was insensitive to the parameters of the thermal excitation impulse, the thickness of the tested sample, and the significant influence of convection cooling on its accuracy. The work was completed with the formulation of general conclusions concerning the conditions for determining the thermal diffusivity of materials with the use of the described method.

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The reserch of the temperature impact in tool-workpiece contact on the quality of the cut at thermofrictional cutting

Sherov K., Sikhimbayev M., Mazdubay A., Sherov A., Rakishev A., Mussaev M., Donenbayev B., Bayzhabaginova G.

Mechanics and Mechanical Engineering

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2017

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Vol. 21, nr 3

755--762

EN

The purpose of the given work is to describe the research methods of the temperature impact in contact on the quality of a cut. The mechanisms of the cut off process by a method of thermofrictional cutting (?FC) are revealed, the drawbacks emerging at the cutoff by a smooth disk in case of application of classical method ?FH are determined and described. The work describes a new mode of the cutoff with a high-frequency break of the contact whose principal difference is a new scheme of heat distribution at the expense of an impulse cycle of heat and refrigeration. Photos of cutting disks made from constructional steels and special equipment mounted on the basis of a lathe are provided, as well as dependence of influence of frequency and the zone size on the mean temperature in the contact are provided.

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Symulacja fizyczna nagrzewania impulsowego stali maraging MS350

Marcisz J.

Prace Instytutu Metalurgii Żelaza

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2016

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T. 68, nr 1

12--18

PL

W artykule przedstawiono wyniki analizy zmian właściwości mechanicznych i mikrostruktury stali maraging MS350 po nagrzewaniu impulsowym. Nagrzewanie impulsowe (chwilowe) do temperatury w zakresie 500÷950°C realizowano metodą oporową i indukcyjną. W wyniku nagrzewania chwilowego materiału po starzeniu standardowym można uzyskać poprawę plastyczności przy nieznacznym obniżeniu wytrzymałości materiału. Wyniki badań wskazały możliwości wytwarzania wyrobów ze stali maraging o podwyższonym poziomie plastyczności oraz wyrobów gradientowych o zmiennej mikrostrukturze i właściwościach na grubości ścianki elementu. Ustalono temperaturowy zakres stosowalności stali maraging poddanej nagrzewaniu impulsowemu.

EN

Results of analysis of mechanical properties and microstructure changes of MS350 maraging steel after impulse heating were presented in the article. Impulse (momentary) heating to the temperature between 500÷950°C was realised by resistance and induction methods. As a results of short-time heating of material after standard ageing, the improvement of plasticity with acceptable decrease in strength can be achieved. Examination results indicate possibilities of production of maraging steel products of higher level of plasticity and gradient products with different microstructure and properties on the cross section of the element. The temperature range for application of maraging steel subjected to impulse treatment was determined.