shaping hardness measurements on the polished specimens show the significant hardening effect due to manganese as an alloy element the hardness increases from hv10 95 u00b1 15 in pure iron to hv10 220 u00b1 10 in fe 10mn and hv10 230 u00b1 10 in fe 20mn because of the face centered cubic u03b3 phase an increase in ductility is also to be expected in the alloys with 10 and 20 mn the electrochemical properties of pure iron and the alloys were determined with the help of impedance spectroscopy under the following conditions specimen temperature 22 9 u00b0 c test medium sbf ph 8 14 reference electrode hg u2014 hg u2014 cl counter electrode platinum test area u00f8 7 4 mm the bode plots are shown in fig8 the eis results show that the susceptibility to corrosion increases significantly due to the additional alloying of manganese an estimate using the impedance values at low frequencies yields a lower value for the alloy with 10 manganese by a factor of 3 5 but the value for the alloy with 20 manganese is lower by a factor of approximately 6 by additional alloying of u201c noble u201d elements x finely distributed u201c noble u201d precipitates are formed which act as cathodic sites and thus lead to increased galvanic corrosion various aspects should be taken into account in the selection of the elements x i the elements should have a limited solubility i e should form precipitates ii the resulting second phases usually intermetallic phases imp should have the highest possible noble metal content so that they also have a strongly cathodic effect and iii biocompatibility should be ensured the binary system of the elements fe and pd makes pd appear especially suitable all the possible imps contain at least 50 at pd.