Bulk material of cubic boron nitride (c-BN) iscommercially achieved via high pressure-high temperature (HPHT)synthesis from h-BN with various catalysts (flux precursors).Since recent investigations indicated c-BN to be the stablemodification at standard conditions there is considerable interestto realise a c-BN synthesis at normal or low pressure. Thus growthconditions allowing high mobility for boron and nitrogen atoms have to be found.The interaction of c-BN with various flux precursors used underHPHT conditions was investigated up to 1300℃ at ambientpressure. The reagents were chosen with regard to their ability tostabilize intermediate reaction products. Metals, nitrides andfluorides were applied for the chemical attack. The morphologicalchanges and degradation of the c-BN crystals were examined byscanning electron microscopy (SEM), X-ray diffraction andinfrared spectroscopy. SEM studies indicate that the degradationBN depends strongly on the nature of the flux precursors. Thoseleading to an intermediate phase during the reaction exhibit distinctetching figures on (111)-planes of c-BN, while reagents leading tothe formation of several products cause an inhomogeneous decay.Since the degradation of c-BN resembles the reversed growth, thereaction mechanism of the interaction of c-BN with reactive meltsallows to establish a growth and degradation model of the cubicphase. The results shall help finding new routes to grow c-BN in alow pressure-melt or chemical vapour deposition process.
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