This paper presents the analysis of research to determine influence of bioglass (15%CaO, 9%P2O5, 76%SiO2 ) addition 0%, 5%, 10% wt. on a structural and mechanical properties of sintered samples based on Co-Cr-Mo alloy. Cylindrical samples 20mm diameter and 10mm length were prepared according to the following scheme:
1) blending of Co-Cr-Mo powder alloy with bioglass addition of 5%, 10%wt. in a ball mill, 2) uniaxial cold compaction at pressure of 600MPa,
3) sintering in the horizontal tube furnace at the temperature 1230C in a dry argon atmosphere, for 1 hour,
4) rotary cold repressing on a PXW 100A press at pressure of 600MPa, number of rotations i=12, with spinning upper tool movement,
5) heat treatment at the temperature of 1230C for 1 hour in argon atmosphere, cooling in the cold area of the furnace.
The measurement of hardness, tensile and compressing strength and ultrasonic tests were performed. The microstructure of cross-sections specimens after sintering, repressing and heat treatment were analysed.
The microstructure of samples after heat treatment exhibited homogeneous distribution of bioglass particles (average size 120 microns) in the Co-Cr-Mo matrix with an average grain size 40 microns.
The compressing tests has shown that an addition to the Co-Cr-Mo matrix 5%, 10%wt. of bioglass caused an increase of the yield strength (from 495MPa to 610MPa for 10% wt. of bioglass), but decrease of UCS and plastic strain of specimens. The tensile strength data (as we assumed) have shown that samples without any bioglass addition received higher mechanical properties in comparing with the glass/metal composites. Non-destructive ultrasonic investigation revealed that the composite samples have lower Young and shears modulus in comparison with samples without any addition. Thus, from the mechanical point of view, the composites with 10% of bioglass addition may be suitable material for further investigation.
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