Research of the recast layer on implant surface modified by micro-current electrical discharge machining using deionized water mixed with titanium powder as dielectric solvent

Abstract Surface modification of Ti using micro-current electrical discharge machining (MC-EDM) technology at various working parameters was conducted in the present study. A significant decrease in amount of surface cracks for modified Ti in deionized water mixed with concentration of 3 g/l Ti powder dielectric solvent was determined. Increasing the concentration of Ti powder to 6 g/l, no micro-cracks were observed on the modified Ti surfaces at current 0.1 A for short-pulse durations (≤50 μs). Moreover, the thickness of the recast layer increases with increasing current, pulse duration and concentration. Under the same working parameters, the thickness of recast layers on modified Ti enhances to approximately 4–11 μm in the concentration of 6 g/l Ti powder dielectric solvent. When Ti modified at different working parameters in deionized water mixed with Ti powder dielectric solvent, the TiO phase was observed within the recast layers. It was found that the modified Ti at current 0.1 A for 30 μs and 50 μs in a 6 g/l concentration of Ti powder dielectric solvent generates a hydrophilicity surface. Therefore, adding a suitable concentration of Ti powder into the dielectric solvent not only prevent the formation of surface cracks and micro-cracks, but also raise the wettability on the surfaces of Ti during MC-EDM modifications.

[1]  H. Toda,et al.  Corrosion resistance and biocompatibility of Ti-Ta alloys for biomedical applications , 2005 .

[2]  B. Bhushan,et al.  Wetting of rough three-dimensional superhydrophobic surfaces , 2006 .

[3]  B. Bhushan,et al.  Wetting study of patterned surfaces for superhydrophobicity. , 2007, Ultramicroscopy.

[4]  Apiwat Muttamara,et al.  Surface modification of tungsten carbide by electrical discharge coating (EDC) using a titanium powder suspension , 2012 .

[5]  J. Weng,et al.  Preparation of bioactive TiO film on porous titanium by micro-arc oxidation , 2012 .

[6]  Tzu-Sen Yang,et al.  Effect of Electrical Discharging on Formation of Nanoporous Biocompatible Layer on Ti-6Al-4V Alloys , 2013, Implant dentistry.

[7]  Jochem Nagels,et al.  Stress shielding and bone resorption in shoulder arthroplasty. , 2003, Journal of shoulder and elbow surgery.

[8]  Ali Alidoosti,et al.  Electrical discharge machining characteristics of nickel–titanium shape memory alloy based on full factorial design , 2013 .

[9]  K. Ou,et al.  Preparation, Characterization, and Properties of Anticoagulation and Antibacterial Films of Carbon-Based Nanowires Fabricated on Surfaces of Ti Implants , 2013 .

[10]  Baoping Cai,et al.  Study of the recast layer of a surface machined by sinking electrical discharge machining using water-in-oil emulsion as dielectric , 2011 .

[11]  P. Layrolle,et al.  Surface treatments of titanium dental implants for rapid osseointegration. , 2007, Dental materials : official publication of the Academy of Dental Materials.

[12]  K. Ou,et al.  High-temperature microstructural characteristics of a novel biomedical titanium alloy , 2010 .

[13]  U. Çaydas,et al.  Electrical discharge machining of titanium alloy (Ti–6Al–4V) , 2007 .

[14]  K. Ou,et al.  Microstructure and phase transition of biocompatible titanium oxide film on titanium by plasma discharging , 2009 .

[15]  S. Hayakawa,et al.  Bioactive titania-gel layers formed by chemical treatment of Ti substrate with a H2O2/HCl solution. , 2002, Biomaterials.

[16]  K. Ou,et al.  Antibacterial nanostructured composite films for biomedical applications: microstructural characteristics, biocompatibility, and antibacterial mechanisms , 2013, Biofouling.

[17]  J. Duszczyk,et al.  Porous NiTi surfaces for biomedical applications , 2012 .

[18]  A. Michaelraj,et al.  Effects of electrical parameters, its interaction and tool geometry in electric discharge machining of titanium grade 5 alloy with graphite tool , 2013 .

[19]  Chao-Sung Lin,et al.  Effects of anodic oxidation and hydrothermal treatment on surface characteristics and biocompatibility of Ti–30Nb–1Fe–1Hf alloy , 2012 .

[20]  D. Pioletti,et al.  Effect of different Ti-6Al-4V surface treatments on osteoblasts behaviour. , 2002, Biomaterials.

[21]  A. Khan,et al.  Influence of electrical discharge machining process parameters on surface micro-hardness of titanium alloy , 2013 .

[22]  C. Chao,et al.  Research of microstructure and mechanical behavior on duplex (α + β) Ti–4.8Al–2.5Mo–1.4V alloy , 2010 .

[23]  T. Miyazaki,et al.  Enhanced osteoblast response to electrical discharge machining surface. , 2012, Dental materials journal.

[24]  M. Janeček,et al.  Characterization of electric discharge machining, subsequent etching and shot-peening as a surface treatment for orthopedic implants , 2013 .

[25]  K. Ou,et al.  Effects of Surface Functionalization on the Nanostructure and Biomechanical Properties of Binary Titanium-Niobium Alloys , 2012 .

[26]  J. Fojt Ti–6Al–4V alloy surface modification for medical applications , 2012 .

[27]  K. Ou,et al.  Effect of electro-discharging on formation of biocompatible layer on implant surface , 2008 .

[28]  H. Rack,et al.  Titanium alloys in total joint replacement--a materials science perspective. , 1998, Biomaterials.