| This paper mainly studies the Preparation of cBN with calcium-boron-silicon systemglass-ceramic binder. On the basis of that investigating the impacts of the composition ofcalcium-boron-silicon system glass-ceramic on the crystallization and exploring itsoptimum sintering schedule as a binder, their combination and sintering system areinvestigated, by sintering cBN with calcium-boron-silicon system glass-ceramic bondingagent.The phase of the sintered samples are analyzed by using X-ray diffraction; The heattreatment system is formulated by using differential scanning calorimetry as a reference;According to Archimedes’ principle the porosity of the samples are tested;Grainmorphology and size of the sintered samples are observed with field emission scanningelectron microscope; The flexural strength of the samples are tested using three-pointbending method.Experimental results show that: In the low boron high calcium area ofcalcium-boron-silicon system, it is easy to get wollastonite phase that this experimenthope to get, and reduce the precipitation of quartz phase and colemanite phase etc,calcium-boron-silicon system can obtain a better crystallization effect when F as anucleating agent and a nucleating agent content of6%. The samples undergo heattreatment with two-stage method, the temperature is set to850℃for liquid-phasesintering, then cool the temperature to750℃with insulation1h for crystallization, hugenumber and small size grains will be getted, the main phase is needle-like wollastonitephase, the flexural strength of the sample is125MPa, the porosity is1.1%.In the binder and cBN sintering, add to concentration of100%cBN, raise thetemperature to875℃for liquid phase sintering and then cool the temperature to750℃w ith insulation1h for crystallization, under this circumstances the binding agent andcBN in the samples have a good combination, the flexuralstrength is102MPa, and theporosity is33.4%. |
