Modulation assistance is widely employed to improve chip management in turning. This process is also known as modulated turning. Modulated turning transforms continuous cutting into intermittent cutting by periodically disengaging the tool tip from the workpiece, resulting in the generation of short, easily managed chips. This novel method improves the...
Water electrolysis plays a pivotal role in achieving a green hydrogen economy by sourcing electricity from intermittent renewable sources. However, the efficiency of the electrolysis process is limited by the sluggish oxygen evolution reaction (OER) kinetics, whereas the kinetics of the hydrogen evolution reaction (HER) are more facile. This thesis...
For next-generation molten salt reactors, there is a need to be able to characterize the corrosion of the molten salts contained within them. One such tool that may be used to accomplish this is a dynamic ref- erence electrode, or DRE. Here, an aqueous dynamic reference electrode (aDRE) was developed,...
Using supercritical CO₂ (sCO₂) as a working fluid has increasingly gained attention in the energy industry. sCO₂ power cycles has various advantages, such as high cycle efficiency, compact turbomachinery, and potential zero CO₂ emission. Along with these benefits, materials degradation issues have also been emphasized in the last decade. Aqueous...
A Cu/Fe-spinel-based oxygen carrier designed at the National Energy Technology Laboratory was studied in order to characterize its physical and chemical behavior with cyclic oxidation and reduction treatments at 800°C for applications in chemical looping combustions. Observations were made on individual particles of the oxygen carrier in-situ using a confocal...
The issue of chloride-induced corrosion of reinforcing steel in concrete and its economic impacts are well-known. Chlorides that cause reinforcement corrosion can be from constituent materials used to prepare concrete or can enter the hardened concrete when the structure is exposed to chloride environments. To minimize the risk of reinforcement...
High early strength (HES) concrete is becoming increasingly used to repair damaged concrete pavement sections. The use of HES concrete enables the repaired pavement to be opened to traffic within hours of placing the concrete. A common approach used for the rapid repair of concrete pavement consists of closing a...
The constituent materials of concrete often contain chlorides. The presence of chlorides in sufficient amounts can disrupt the passive layer, also known as the passive film, that protects the reinforcing steel in concrete. This disruption can lead to premature corrosion of the reinforcing steel in concrete. To minimize the risk...
Chloride-induced corrosion is one of the primary causes of the degradation of reinforced steel in concrete structures. Currently, the rapid chloride permeability test (RCPT) is the most specified method to determine the concrete’s resistivity to chloride ingress, thus a determining factor in assessing the durability of concrete. While it is...
Significant progress has been made over the past 20 years in developing models to estimate the service-life of reinforced concrete systems. The basic understandings of the mechanisms that control the transport of ions and moisture in concrete systems have been well researched and models for determining corrosion initiation, specifically chloride-induced...