Synthesis of nano-polycrystalline diamond (NPD) and its application to ultrahigh-pressure studies

Abstract

Since the first report of synthesis nano-polycrystalline diamond (NPD), efforts have been directed to synthesize larger bodies of NPD with higher quality, using Kawai-type multianvil apparatus. NPD has extraordinarily high hardness, peculiar nano-texture and high transparency, which has also been found to have very high elastic stiffness, high toughness, and high wear-resistance. These characteristics of NPD are important in applications as anvils for various types of high-pressure apparatus toward generation of higher pressures and temperatures with greater accuracies. Here, we review current status of synthesis of NPD, its physical properties, and some preliminary results in applications to high-pressure studies.