Investigation of the Effect of Pulsed Power During Electrochemical Surface Modification of Aluminum and Titanium Alloy
Location
Loosemore Auditorium
Description
PURPOSE: Aluminum and especially titanium alloy have become the focus of many studies due to their high strength to weight ratio and biocompatibility. Surgical implants need to have a hydrophilic nature when tissue growth is desired, while they need to be hydrophobic if tissue/microbial growth is not expected. Thus, there is a need to control the wettability of these metals. SUBJECTS: This study used a sodium chlorate electrolyte to control the wettability of 1 inch by 3 inch aluminum and titanium alloy samples using an electrochemical surface modification (ECSM) process. METHODS AND MATERIALS: Duty cycle, frequency, and ECSM duration were modified while voltage was held constant at 10 V. Duty cycles of 25%, 50%, 75%, and 100% (or DC) and frequencies of 1 kHz and 100 kHz were used. Time was changed to allow the samples to have an equal active time with 2000, 1000, 667, and 500 seconds for 25%, 50%, 75%, and 100% duty cycles, respectively. ANALYSES: A first principles based theoretical model was developed in this study to predict the pulse power setting needed to achieve the desired wettability in the samples by measuring the sample mass before and after ECSM. The model was validated with experimental results. RESULTS: The surface's wettability switched from hydrophilic to hydrophobic after the sample was heated in a furnace. Both the metals showed a change in contact angle behavior after evaporation of the residual water. CONCLUSIONS: This study allows for the use of ECSM as a technique to modify the surface of implants with controlled wettability for improved osseointegration.
Investigation of the Effect of Pulsed Power During Electrochemical Surface Modification of Aluminum and Titanium Alloy
Loosemore Auditorium
PURPOSE: Aluminum and especially titanium alloy have become the focus of many studies due to their high strength to weight ratio and biocompatibility. Surgical implants need to have a hydrophilic nature when tissue growth is desired, while they need to be hydrophobic if tissue/microbial growth is not expected. Thus, there is a need to control the wettability of these metals. SUBJECTS: This study used a sodium chlorate electrolyte to control the wettability of 1 inch by 3 inch aluminum and titanium alloy samples using an electrochemical surface modification (ECSM) process. METHODS AND MATERIALS: Duty cycle, frequency, and ECSM duration were modified while voltage was held constant at 10 V. Duty cycles of 25%, 50%, 75%, and 100% (or DC) and frequencies of 1 kHz and 100 kHz were used. Time was changed to allow the samples to have an equal active time with 2000, 1000, 667, and 500 seconds for 25%, 50%, 75%, and 100% duty cycles, respectively. ANALYSES: A first principles based theoretical model was developed in this study to predict the pulse power setting needed to achieve the desired wettability in the samples by measuring the sample mass before and after ECSM. The model was validated with experimental results. RESULTS: The surface's wettability switched from hydrophilic to hydrophobic after the sample was heated in a furnace. Both the metals showed a change in contact angle behavior after evaporation of the residual water. CONCLUSIONS: This study allows for the use of ECSM as a technique to modify the surface of implants with controlled wettability for improved osseointegration.