~~The fatigue life and reliability of components for modern drilling technologies are restricted by severe environmental conditions. The mechanical strain caused by drilling through hard formations in combination with increasing temperatures due to large drilling depths typical for depth geothermal wells and in corrosive media are particular critical for metallic materials. Therefore for testing materials a suitable test rig which enables to mimic the simultaneous influence of multiaxial fatigue loading elevated temperatures and corrosive environments is necessary. Because of the complexity of this type of testing the use of non-contacting 3D measurement techniques and thermography was considered. Also a special specimen geometry was developed. The influence of surface quality temperature loading conditions and corrosion on the fatigue life and reliability of one Cr-Mn-N austenitic steel and alloy 718 has been evaluated. These materials are commonly used in drilling applications due to their high strength high ductility non-magnetic behavior and good corrosion resistance. The failure mechanisms were studied in detail by means of scanning electron microscopy and x-ray diffraction.