Microstructural mechanical properties and yield point effects in Mo alloys

The mechanical properties of two phase Mo–Si–B alloys were analyzed with nanoindentation techniques and atomic force microscopy. A nanoindenting atomic force microscope allows local determinations of hardness and modulus of the T2 phase and Mo(ss) phase. The T2 phase and Mo(ss) phase in these alloys show a hardness of 21 and 8.5 GPa, respectively. The modulus of the T2 phase is nearly 10% higher than that for the Mo(ss) phase. Large pop-ins are found during indenting in the T2 phase but not in the Mo(ss) phase which has a higher surface roughness.