Formation of Nano-structure Material Using Chaotic Theory and its Physical Properties

1997 Fiscal Year Final Research Report Summary

• Project/Area Number: 07455300
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Metal making engineering
• Research Institution: KYOTO UNIVERSITY
• Principal Investigator: ISHIHARA Keiichi Kyoto University, Graduate School of Energy Science, Associate Professor, エネルギー科学研究科, 助教授 (30184550)
• Co-Investigator(Kenkyū-buntansha): OTSUKI Toru Kyoto University, Institute of Advanced Energy, Associate Professor, エネルギー理工学研究科, 助教授 (10026148) ; SHINGU Hideo Kyoto University, Graduate School of Energy Science, Professor, エネルギー科学研究科, 教授 (20026024)
• Project Period (FY): 1995 – 1997
• Keywords: chaos / mechanical alloying / sputter / repeated deformation / alloying / kinetics

Research Abstract

It is reported that the formation of Fe-Ag nano-layred material can be produced by repeated pressing and rolling ; the repeated plastic deformation of powder and foil. The specimen producedby the repeated rolling is observed the giant magneto-resistance (GMR). The GMR effect has been only reported in the multilayr material the each layr thickness of which is less than 1nm. While the specimen produced by the repeated rolling shows GMR effect, even if the thickness is about 50nm.
In this research, the multilayr samples whose layr thickness from 10nm to 100nm were produced by magnetron sputtering. In these material, only 10nm sample shows GMR,0.15% at 77K.While the 70nm sample produced by the repeatedrolling shows GMR,4.5% at 77K.
Since the samples produced by the repeated rolling have the distributed layr thickness, The inhomogeneous multilayr sample produced by sputtering is produced. Each layr thickness was simulated by the value which was measured in the repeated rolling sample. This sample shows GMR,1.5% at 77K.
Consequently, GMR of homogeneous multilayr sample is larger than that of chaotic multilayr sample.