EFFECT OF ORIENTATIONAL STRENGTHENING OF POLYMERIC MATERIAL ON MECHANICAL PROPERTIES OF PRODUCTS

The research deals with the problem of mathematical modeling of bending of polymeric beams. Polymeric materials today play a leading role in the manufacture of various parts in all industries. In this connection it is important to determine the characteristics of such products and predict their behavior in various conditions. Mechanical properties of the strengthened polymeric parts do not meet Hooke's law; therefore, the problem of the determination of their stress and strain state cannot be solved by classical methods of strength of materials and theory of elasticity. It is difficult to predict behavior of strengthened polymeric parts under loading, so it is important to evolve the method for calculation stress and deformation in most frequently occurring situation such as bending. Aim: The purpose of the research is to obtain a mathematical model that describes stress and strain in bending doubly-supported beams made of polymeric materials. Materials and Methods: Experimental research of bending doubly-supported beams was performed using samples of hardened high-density polyethylene according to the standard method of static bending test for plastics. Originality: The mathematical model of bending of polymeric beam under load force applied to its middle section is evolved. The mathematical model describes the dependence of stress and strain on the loading force at bending of solid and hollow polymeric beams. The expressions for calculating stress occurring in the material of the beam and its deformation are obtained. Results: Experimental studies have confirmed the correctness of the developed mathematical model which allows offering the obtained analytical expressions for calculation plastic parts for strength and rigidity. The results can be used in the design of structural elements of machines and appliances, products of light industry.