Estimation of damage development and the time of failure of cutting inserts made of hard alloys and superhard composites by chemography methods

Abstract

The results of theoretical and experimental studies aimed at identifying hidden defects in the structure of hard alloys and superhard composites used in the manufacture of cutting tools in order to control and predict gradual and sudden failures of cutting inserts.Damage control of cutting inserts is carried out by microscopic analysis. Deeper damage to the structure can be detected using the method of chemographic imaging. The proposed method is based on obtaining photographs of the oxidative reactions of materials of ultra-low concentrations occurring on the surface of solids under thermobaric loading.Before the moment of a sharp release of the energy of destruction, chemical processes of ultra-low concentrations are activated. Chemography allows to fix the zones where the incipient microcracks and microdefects are ready to actively develop, which can lead to the onset of macrodamage and failure to work.The chemographic image of the plate obtained as a result of the study is compared with the reference sample, as a result of which it is possible to assess the initial defect state of the material and predict the further period of the plate’s operation.The criterion for the existing defects and imperfections in the structure is the change in the blackness index of the chemographic image, the minimum value of which indicates a minimum of structural defects and internal defects in the material under study.The results allow to propose a new method for controlling the surface of cutting plates, which can be easily implemented in any machine shop, which makes its application very promising