Change of magnetic properties in austenitic stainless steels due to plastic deformation

Austenitic stainless steels, investigated in this research, belong into a group of the so-called high-alloy TRIP (Transformation Induced Plasticity) steels. The nondestructive evaluation (NDE) methods were used for determination of plastic deformation influence in investigated materials. The NDE methods permit products to be inspected throughout their service life, to determine when to repair or replace a particular part. The main goal of this study was to measure and thus separate different levels of applied plastic deformation of selected conductive biomaterials. Two different devices were used to evaluate the effect of plastic deformation. The first device was commercially available magnetic field sensor GF708. The second device was Magnet Physik, on which is possible to determine magnetic quantities (remanence, coercivity), make measurements with surrounding coils to determine the magnetic mean values and measure at temperatures up to 200°C. Both of those devices are suitable for measuring the magnetic properties. Effect of plastic deformation was observed by the light microscope, as well.