Physics Journal of the Indonesian Physical Society
SHIFTING OF HALL-PETCH EFFECT IN SUPER AND ULTRA-HARD NANOCOMPOSITES
Keba Moto, Z. Abubakar, L. Setiarini, A. Faisal, H. Nurhadi
Material Technology Group, Departemen Fisika, Universitas Indonesia, Kampus Baru Depok, 16424, Indonesia and
The Mochtar Riady Centre for Nanotechnology and Bioengineering Karawaci-Banten, Indonesia
Nanocomposites coating such as nc-TiN/a-Si3N4 has been produced as hard coating for cutting tools industries. Novel properties such as high hardness, toughness and thermal stability have set up this coating material to have a wide range of application. However, the origin of these novel properties is still unclear and left as scientific problems. In order to solve these problems, we present a mechanical system modeling of nanocrystalline that can clarify the experimental result in obtaining super- and ultrahard coatings. It is obtained that the influence of amorphous content and nanocrystallite size in the nanocomposite nc-TiN/a-Si3N4 has form a similar effect to the Hall-Petch relation, in a new view point. The model demonstrates that in nc-TiN/a-Si3N4 the Hall-Petch relation occurs in a different way, that is, this relation has two vital parameters (amorphous content and crystallite size) which create a shifting on the Hall-Petch relation in common nanostructure design.