Wear Properties of a Shock Consolidated Metallic Glass

Powder flakes prepared from 50 ~m thick melt spun ribbons of Markomet 1064 (Ni Mo Cr B1 wt%) were shock consolidated in the unannealed and anne~f~~ co~§iti§n. "lhe unannealed flakes (microhardness g33 kg/mm2) are amorphous while flakes annealed at 900°C for 2 hours have an fcc structure with a grain size of 0.3 ~m and microhardness of 800 kg/mm2. The shock consolidated amorphous powder compact (250 kJ/kg shock energy) shows no crystal peaks in an X-ray diffractometer scan. Compacts of annealed powder (400 to 600 kJ/kg shock energies) contain amorphous material (18-21 %) which was rapidly quenched from the melt formed at interparticle regions during the consolidation process. The microhardness of the amorphous interparticle material is 1100 kg/mm2. Wear properties of the compacts measured in low velocity pin on disk tests show low average dynamic friction values (~.03). The 60 hour cumulative wear appears to correlate with the energy of shock compaction and surface porosity of the compacts rather than the metallic glass content.