Spheroidization of Bioceramic Powders in a Radio Frequency Plasma
Inductively coupled radio frequency (RF) plasma spraying, powered by high-frequency oscillating electrical current, performed an important role in fine powder manufacture. It was used in the present study to prepare fine spherical bioceramic powders of hydroxyapatite (HA) whose chemical composition similar to those of natural bone. The as-sprayed powders consisted of both micron-sized spherical particles and nano-sized particles. In addition to the spheroidization effect, rf plasma treatment led to the decomposition of HA into secondary calcium phosphate phases including tri-calcium phosphate (TCP), tetra-calcium phosphate (TTCP) and calcium oxide (CaO). The microstructure investigation showed that the spheroidized particles were either fully dense or hollow structure with a shell. The reason for the formation of hollow spheres was contributed to the higher density of the solidifying surface layer compared with the molten phase during solidification.
J.L. Xu K.A. Khor R. Kumar
School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore Department of Environmental Engineering, Montana Tech of the University of Montana, Butte, MT, USA
国际会议
北京
英文
2007-05-14（万方平台首次上网日期，不代表论文的发表时间）