Application of G. Lame’s and J. Gielis’ formulas for description of shells superplastic forming

Abstract

The paper shows that the contour of a sheet blank at all stages of superplastic forming can be described by application of the universal equations known as a "superformula" and "superellipse". The work provides information on the ranges of values of the coefficients entering these equations and shows that their magnitudes make it possible to additionally determine the level of superplastic properties of the workpiece metal, the shape of the shell being manufactured, the stage of superplastic forming, and the presence of additional operations to regulate the flow of the deformable metal. The paper has the results of approximation by the proposed equations of shell contours that manufactured by superplastic forming by different methods.

Experimento sencillo para el modelamiento de la interfase de reacción en la descomposición de sólidos

“…El presente trabajo formula un método experimental sencillo para enseñar sobre las reacciones de descomposición (comprendido en un sentido lato) de los sólidos a través del modelamiento geométrico de la interfase de "reacción" en la sublimación del naftaleno por ecuaciones matemáticas de Lamé (Matsuura, 2014;Anishchenko et al, 2018;Borisenko et al, Research, Society and Development, v. 12, n. 1, e25812139805, 2023(CC BY 4.0) | ISSN 2525-3409 | DOI: http://dx.doi.org/10.33448/rsd-v12i1.39805 2020Boualem & Brouzet, 2015), para la ilustración de este proceso (más concretamente, centrándose en la calcinación de carbonatos, un proceso de gran relevancia industrial).…”

Contact-deformation mechanism of boundary friction

“…The authors of [13,14] proposed theoretical dependences for a wear testing method using a standard four-ball scheme with determination of wear resistance parameters. The approximating function [15] of the wear spot diameter on the friction path obtained by the results of wear tests was taken as the base of the method. The general methodology of this study can be used to develop a theory of test methods for other geometric schemes.…”

Study of some aspects of refining process physics of large-sized details precision surfaces

“…The third theory [18][19][20] explains surfaces refining process by abrasive grains as purely thermal, i.e. due to friction of abrasive on the surface to be processed temperature of the surface layer increases significantly which makes the surface layer liquefy and due to the surface tension forces 'troughs' are filled with 'protrusions' forming smooth surface and instantly solidified layer.…”