Last developments in indentation and computer simulation techniques for the evaluation of mechanical properties (hardness, fracture toughness) of materials are popular because the test conduction is simple. There is no need for precise and expensive specimens of specific geometry, standard tools (indenters) and equipment are used; a lot of measurements can be conducted on relatively small testpieces. Last studies have shown the possibility for the evaluation of the materials residual stresses using a combined indentation–simulation testing technique. The present study is an attempt to measure residual stresses arising in a carbide composite (conventional hardmetal and cermet) using this combined technique. Conventional steels are tested for comparison and validation of the testing technique. An improved simulation algorithm for the assessment of the residual stresses in materials (steels, carbide composites) by load and depth sensing indentation with spherical indenter of specified properties is proposed. The experimental validation of simulations is performed. Spherical indentation results are proved by scanning electron imaging and 3D optical microscopy. The results of the simulations are in a good agreement with experimental indentation data. The used method does not require imaging of the indentation impressions and testing of the stress-free specimen for the localized measurement of the residual stresses. It can be used as a reliable express tool for the assessment of the residual stresses with some approximations regarding friction peculiarities of the Hertzian contact between the spherical indenter and specimen surfaces.
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