Electrochemical Post-Processing of Zn-Ni Deposition on Steel Substrate for Reliable Composition; Formulating a Framework for Technical Advantage and Technical Advancement for Materials Optimization in Competitive Sports

Leveraging materials science under the consideration of the ethical implications is a powerful way to revolutionize current engineering design. Aerospace materials must withstand extreme environments during use and current state-of-the-art stress corrosion resistant coatings are toxic, so there is a need for safe engineering design. To improve the stress corrosion resistance of a protective coating on a structural material, preferential reverse plating of a novel coating composition was utilized to tailor the material properties to endure a damaging environment. Similarly, in the late 2000s, the sports industry was introduced to materials optimization, but this made technical doping a popular concern. A sociotechnical framework is needed to distinguish between technical advantage and technical advancement to protect athletes, athletics, and engineering design. Corrosion engineering is fundamental to materials engineering because of the pervasiveness and presence of water for in-use conditions of most engineering applications. Technical doping emphasizes the significance of being cognizant of the complex interactive effects of designing a novel material with a specialized property profile.
Rolls-Royce Corporation has found that stress corrosion cracking of aerospace application structural materials due to in-use conditions is a limitation which can be remedied by plating a coating on the substrate with improved corrosion resistance. Zn-Ni is the novel composition for corrosion resistant coatings to replace the state-of-the-art Cd coatings which are toxic to humans. The optimized ratio of Zn to Ni has not yet been identified and more than that, a processing technique which reliable reproduces the same composition repeatedly has not yet been identified either. Thus, this project aims to explore electrochemical post-processing techniques of Zn-Ni deposition on a steel substrate for a reliable composition. This experimentation was tailored to be easily implemented in the existing methodology employed by Rolls-Royce Corp. by relying on reversing the current in the electrodeposition apparatus. To identify the viability of this process, variable current and exposure were used to characterize the electrochemical properties of the coating which were analyzed through electron microscopy.
The objective was to consistently raise the value of the open circuit potential (OCP) of Zn-Ni coated steel to be in the immunity region for stress corrosion cracking. It was found that current densities lower than 0.03A/cm2 did not selectively dissolve the coating at all and therefore, a more aggressive current density was required. But a greater current density of 0.01A/cm2 stripped the entire coating off the substrate. Neither strategy achieved the immunity region when using the experimental setup that Rolls-Royce Corp. currently uses, but when the bath solution was replaced from the deposition solution to a NaCl solution, a galvanostatic hold and stirring coupled together enabled the dissolution to achieve the immunity region.
Athletic performance enhancement is inherent in sports equipment, but it is unclear to what degree improved performance is considered a positive product of technological advancement or an unfair technological advantage. Technical doping is a nebulous concept that has not been further clarified or unanimously defined by the array of regulatory agencies in athletic administration. This is evidenced by the lack of a comprehensive framework to guide materials optimization in athletics to capture the multi-faceted and compounding nature of the sports technology network. In this work, actor-network theory was employed to characterize the relationships between different actors in the sports realm in the contexts of equal accessibility of the technology, athletic safety, the external interaction of the technology to the environment, and the engineering design process. These were defined through the analysis of case studies of past instances of technical doping.
The two instances of sensationalized technical doping include the Speedo LZR Racer in swimming and the Nike Vaporfly in running. Both technologies were banned after production and release to the public market. Thus, the regulatory bodies over sports technology do not have a clear framework to guide manufacturing, but also permitted these technologies to enter the public market and global competitive stage. Despite effectively protecting the spirit of the game once enacted, this ban did not consider the sociotechnical ethics in its regulation, such as the economic barrier inhibiting equal accessibility, the concern for the physical toll of use, the difference between biomechanical and mechanical advantage, nor the implications for future engineering design. Current regulation lacks the consideration of the product of legal bans, athletic experience, and the responsibility to preemptively guard the spirit of the game. It is abundantly clear that a defined framework designed around technology ethics is needed to help inform the future of sports technology.
In both the technical exploration of the electrochemical reverse plating processing of Zn-Ni for corrosion resistance and the sociotechnical analysis of technical doping, the consideration of the comprehensive effects on the human experience of a technology was neglected. Zn-Ni was implemented to replace Cd which was employed despite being toxic. Sports regulation lacks the sociotechnical perspective making technical doping bans miss the point of advocacy.

School of Engineering and Applied Science

Bachelor of Science in Material Science and Engineering

Technical Advisor: James Fitz-Gerald

STS Advisor: Pedro Francisco

Technical Team Members: Thomas Domer, Emma Laubengayer, Morgan Small, Leah Smith, Alexandra Uy