Effect of pretreatment of starting diamond powder in a hydrogen medium on the hardness of polycrystals obtained

   
V.Vereschaka,
 
A.A.Bochechka
 

I. M. Frantsevich Institute for Problems of Materials Science of the NAS of Ukraine, Krzhizhanovsky str., 3, Kyiv, 03142, Ukraine
Electron Microscopy and Strength of Materials - Kiev: Frantsevich Institute for Problems of Materials Science NASU, 2013, #19
http://www.materials.kiev.ua/article/775

Abstract

The results of investigation of the microstructure and hardness of two sets of single-phased diamond polycrystals obtained at Р = 8 GPа and Т = 1700—2100 0С on the basis of diamond powders sizing 1/0 and 20/14 mcm which were prior treated in a hydrogen medium are presented. It has been shown that plastic deformation of diamond grains under sintering proceeds via perfect dislocations and multiple twinning. Also, at Т >1700 0С rotary deformation takes place. Hardness reaches 81 and 94 GPa for fine- and coarse-grained samples, respectively. Full text download


DEFORMATION, DIAMOND, DISLOCATION, GRAIN SIZE, HYDROGEN, SINTERING, TWINNING