Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (41권6호 301-307)

Effects of Impact Velocity on Crystallization and Activation Energy of Cu-based Bulk Metallic Glasses in Kinetic Spray Coating

저온 분사 코팅 공정에서 충돌속도에 따른 CuNiTiZr 벌크 비정질 소재의 활성화 에너지와 결정화 거동 분석

윤상훈;배규열;김정환;이창희;
Yoon, Sang-Hoon;Bae, Gyu-Yeol;Kim, Jung-Hwan;Lee, Chang-Hee;

한양대학교 신소재공학부 저온 분사 코팅 연구실;
Kinetic Spray Coating Laboratory, Division of Materials Science & Engineering, College of Engineering, Hanyang University;

DOI : 10.5695/JKISE.2008.41.6.301

Abstract

In this paper, nanocrystallization of CuNiTiZr bulk metallic glass (BMG) subjecting to a kinetic spraying, dependent on impact velocity, was investigated by numerical and experimental approaches. The crystallization fraction and nucleation activation energy of initial feedstock and as-deposited coating were estimated by DSC and Kissinger method, respectively. The results of numerical modeling and experiment showed that the crystalline fraction and nucleation activation energy in BMG coatings were depended on kinetic energy of incident particle. Upon impact, the conversion of particle kinetic energy leads to not only decreasing free energy barrier but also increasing the driving force for an amorphous to crystalline phase transformation. The nanocrystallization of BMGs is associated with the strain energy delivered by a plastic deformation with a high strain rate.

Keywords

Kinetic spray;High-resolution electron microscopy (HREM);Metallic glasses;Crystallization;Superplasticity;