Connection of Odkvist Parameter and Values of Microhardness when Hardening by Plastic Deformation

摘要

In the work the authors put the emphasis on the fact that development of new strengthening technologies, in particular by methods and ways of metal forming, requires finding of connections between the practical measured parameters of hardening and results of mathematical modeling of technological processes. As results of pilot studies the authors have chosen the parameter of microhardness and its distribution on the section of products. As results of theoretical and mathematical modeling of real productions they have chosen Odkvist parameter. With use of various mathematical transformations and physical assumptions the authors reveal the connection between Odkvist parameter and one of mechanical parameters of products - microhardness. They show that creation of the specified dependence requires carrying out two elementary experiments with sample material. By the results of these works one can define the corresponding coefficients which are the parts of the equation of connection between Odkvist parameter and microhardness. As an example, the authors show the connection of Odkvist parameter with microhardness parameter for gradient-reinforced products processed by the method of strengthening complex local loading of the center of deformation. They give a short review of the technology for receiving details like plugs considered in the example. At the same time in a body of a product (plug) one gets the strengthened structure, gradient from an external surface, which conforms to operational requirements better, than received when processing by traditional ways of hardening. As a result in the work the authors show that Odkvist parameter is the important characteristic of any strengthening technology and one can use it as a universal criterion when comparing results of theoretical and pilot studies.