NATURE OF THE REAL STRUCTURE OF GRAPHITE-LIKE BN AND ITS TRANSFORMATION INTO A WURTSITE MODIFICATION UNDER IMPACT COMPRESSION

The dependence of the interlayer distance d on the degree of unidimens ional disorder gamma in graphite-like BN was determined. It was establ ished that d = 0.33273 + 0.00005 nm at 20 degrees C in the perfectly o rdered structure (gamma = 0); the value of d increases uniformly with increase of gamma, and at gamma = 1 it equals 0.343 +/- 0.001 nm. It w as also established that the yield of wurtsite phase produced by impac t compression of the graphitelike modification sharply decreases with increase of gamma, and for gamma > 0.2 it becomes equal to zero. This result is explained in terms of the nature of martensitic transformati ons in layered structures.