中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 25 No. 8 August 2015 |
（1. Department of Mechanical Engineering Science, University of Johannesburg,
Auckland Park Kingsway Campus, Johannesburg 2006, South Africa;
2. National Laser Centre, Council for Scientific and Industrial Research (CSIR), Pretoria 0001, South Africa）
Abstract:The laser metal deposition (LMD) was conducted on copper by varying the processing parameters in order to achieve the best possible settings. Two sets of experiments were conducted. The deposited composites were characterized through the evolving microstructure, microhardness profiling and mechanical properties. It was found that the evolving microstructures of the deposited composites were characterized with primary, secondary and tertiary arms dendrites, acicular microstructure as well as the alpha and beta eutectic structures. From the two sets of experiments performed, it was found that Sample E produced at a laser power of 1200 W and a scanning speed of 1.2 m/min has the highest hardness of HV (190±42) but exhibits some lateral cracks due to its brittle nature, while Sample B produced at laser power of 1200 W and a scanning speed of 0.3 m/min shows no crack and a good microstructure with an increase in dendrites. The strain hardening coefficient of the deposited copper composite obtained in this experiment is 3.35.
Key words: copper composites; laser metal deposition; mechanical properties; strain hardening
