Laser assisted fabrication of Co on Ti for bio-implant application
|Jyotsna Dutta Majumdar 1, S. M. Ganeshan 1, Indranil Manna 1, A. K. Nath 2|
1. Indian Institute Of Technology,Kharagpur (IIT), Kharagpur, India
Laser assisted fabrication is a materials processing technique that utilizes high-power lasers to melt the material in the form of a powder or wire, controlled deposition of the molten metal in a layer-by layer fashion and subsequent solidification in the controlled atmosphere to induce a pre-determined shape of a component. The process has successfully been employed for the fabrication of metallic, ceramic and polymer materials. In the present study, attempts have been made to fabricate a Co layer on the surface of Ti substrate (with a compositionally graded interface) by laser assisted fabrication technique. Laser assisted fabrication was carried out by melting of Co powder (of 25 mm particle size) with a continuous wave CO2 laser and subsequent deposition of molten metal on Ti substrate in a layer by layer fashion using Ar as shrouding environment to avoid oxidation. The process variables were applied power density, scan speed and number of layers. During the development of 1st layer, laser power and scan speeds were varied to develop a compositionally graded interface. After fabrication, a detailed microstructural study of the surface and cross section of the fabricated components was carried out using optical and scanning electron microscopy to understand the influence of laser parameters on microstructure of the surface and interface between the successive layers. X-ray diffraction study and energy dispersive spectroscopic analysis were conducted to see if non-equilibrium cooling associated with the process has caused formation of any new phase or segregation of elements in the microstructure. Finally, the characteristics of the fabricated component have been correlated with the process parameters to optimise the processing zone for the fabrication of 316L. The mechanical properties of the fabricated components have been evaluated using microhardness testing machine and correlated with the microstructure.
Presentation: oral at E-MRS Fall Meeting 2005, Symposium F, by Jyotsna Dutta Majumdar
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-05-23 07:19 Revised: 2009-06-07 00:44