Engineering Commons^™

Retrofit Of Corroded Corrugated Metal Culverts Using Gfrp Slip-Liner, Rahulreddy Chennareddy

Civil Engineering ETDs

Culverts are water conveyance structures, typically used to allow water flow and maintain a balance between the flow streams without interrupting structures such as highways and bridges. Corrugated metal pipes (CMPs) have been used as culverts in North America since the 1950s because of their low cost and simple construction method. Today, the corrosion of CMPs is a major problem faced by all U.S. Departments of Transportation. There is an urgent need to provide an efficient solution, one that is corrosion-resistant, to retrofit thousands of corroded CMPs across the country. High specific strength, high strength to weight ratio, corrosion resistance, …

Application Of Bayesian Networks To Integrity Management Of Energy Pipelines, Wei Xiang

Electronic Thesis and Dissertation Repository

Metal-loss corrosion and third-party damage (TPD) are the leading threats to the integrity of buried oil and natural gas pipelines. This thesis employs Bayesian networks (BNs) and non-parametric Bayesian networks (NPBNs) to deal with four issues with regard to the reliability-based management program of corrosion and TPD. The first study integrates the quantification of measurement errors of the ILI tools, corrosion growth modeling and reliability analysis in a single dynamic Bayesian network (DBN) model, and employs the parameter learning technique to learn the parameters of the DBN model from the ILI-reported and filed-measured corrosion depths. The second study develops the …

The Effect Of Rapid Solidification And Heat Treatment On Microstructure And Electrochemical Properties Of Advanced Biomaterial Co-Cr-Mo-C Alloy, Hamid Reza Erfanian Nazif Toosi

Theses and Dissertations

Co-Cr-Mo-C alloys have been used for implant materials for decades because of their strength, corrosion resistance, wear resistance, and biocompatibility. To develop durable low-friction joint replacement implants, it is important to understand the solidification structure and properties of these materials. While HCP phase is the thermodynamically stable phase in these alloys, they maintain their high-temperature γ-FCC matrix and coarse dendritic structure on cooling to room temperature when cast by conventional methods. In this research, a wedgeshaped copper chill mold was used to examine the effect of cooling rates from 10 K/s to 450 K/s on the microstructure, HCP fraction, and …

A Study And Simulation Of Flux Induced Corrosion In Copper Tubing Used For The Distribution Of Potable Water, Daniel O. Benham

Materials Engineering

Water side corrosion within copper plumbing can occur due to a wide variety of unwanted circumstances. Through the controlled immersion of six ¾” copper tubing samples with five utilizing a unique industry standard soldering flux, this investigation associates residual flux deposits with the initiation of pitting in copper. Water stagnation in a copper potable water distribution system, typically associated with an infrequently used faucet, is a condition highly prone to copper pitting. A test apparatus designed to produce a partially stagnant flow condition with scheduled electrolyte flushes every 3 days was developed and constructed to contain 6 test samples for …

Effect Of Solder Joint Flux Residue On Medical Guide Wire Performance, Rebecca Lisberg, Enlly Bugarin Rodriguez

Materials Engineering

The effect of residual soldering flux on the mechanical properties of 304 stainless-steel core medical guide wires was analyzed. A soldering process joins the metallic components of the distal end of a medical guide wire product. Acidic soldering flux is used to prepare the surfaces of the metallic substrates. Manufacturing protocol utilizes an ultrasonic bath to remove excess flux from the soldered joints. Sample groups underwent different levels of cleaning: no cleaning, partial cleaning, and full ultrasonic bath cleaning to obtain varying residual flux levels. Experimental sample groups underwent corrosion acceleration in an environmental chamber at 37°C and 85% relative …

The Influence Of Heat Treatment On Corrosion Behavior Of Martensitic Stainless Steel Uns 42670, Armen Kvryan

Boise State University Theses and Dissertations

Ceaseless demand for lighter, faster, and more efficient aircraft has been one of the greatest driving forces behind bearing steel innovations. Recent studies demonstrate that corrosion is one of the leading causes of bearing failure in both military and commercial aircraft. High-performing bearing steels are available but are not being used in US military applications due to high cost and security issues when steels are produced outside of the continental United States. One approach to address this issue is to engineer steels that are cost-efficient and heat treated for corrosion resistance, long wear life, etc.

This dissertation presents information on …

An Experimental And Numerical Investigation Of Flow Accelerated Flibe Corrosion, David B. Weitzel

Nuclear Engineering ETDs

Renewed interest in molten salt reactor technology has brought to light the need for a better understanding of FLiBe corrosion. To this end a flowing FLiBe corrosion test loop was designed to test the flow effects of FLiBe corrosion. The loop consists of a pump, melt tank, and stainless-steel tubing assembly that heats the molten salt to high temperatures and circulates it over test specimens. The experiment has been constructed and has completed initial shakedown testing.

To support the flowing FLiBe experiment, a numerical corrosion model that couples FLiBe electrochemistry, solid metal diffusion, and mass transport was implemented. The model …

Controlled Release Of Corrosion Inhibitors: Zinc And Magnesium Containing Sodium Chromate, Andrew Thomas

Williams Honors College, Honors Research Projects

Corrosion can be combated by multiple methods, where the primary purpose is to minimize degradation of metal surfaces. Corrosion inhibitors are one of the most effective methods of corrosion protection. Inhibitors are substances that minimize corrosion in aggressive environments, with only a low concentration required. The inhibitors are chemically adsorbed on the surface of the metal and a protective thin film is formed . The mechanism of the inhibitors could be described as anodic, cathodic, or a mix of the two. Anodic inhibitors, also known as passivation inhibitors, alter an anode reaction. Corrosion potential of the metal is shifted to …

Benefits Of Aluminum: Comparing The Common Materials In The Bar Grating Industry, Joanthan Geiser

Williams Honors College, Honors Research Projects

The main aim of this project is to study the wholistic behavior of the 6xxx series of aluminum for use in the bar grating industry for a waste water treatment environment. This project will study the comparison of certain aluminum 6xxx series alloys to steel, stainless steel, and glass fiber-reinforced plastic. While comparing these materials, it will look at the mechanical properties such as modulus of elasticity, yield strength, and ultimate tensile strength. In addition, the available corrosion test of the 6xxx series aluminum alloys will be examined to find a generalization of the corrosion behavior for this series. A …

Cataloging The Degree Of Sensitization Via Electrochemical Reactivation For Studying The Corrosion Behavior Of Inconel 718, Austenitic, And Duplex Stainless Steels, Bradley Lynes

Williams Honors College, Honors Research Projects

Corrosion resistant materials can be expensive, but usually reduce the life cycle cost of metallic assets. However, negligent sensitization of these materials can lead to aggressive, intergranular corrosion. Using the methodology of the double loop electrochemical potentiokinetic reactivation (DL-EPR), this project investigates different steel reinforced bars and Inconel to determine the degree of sensitization after a heat treatment of 900°C for 2 hours. The purpose of this research is to validate and determine the appropriate test parameters for performing further DL-EPR test in the future. Additionally, the kinetics observed for each sample during the DL-EPR test will be analyzed and …

Stress Corrosion Cracking Of Stainless-Steel Reinforced Concrete, Nathan Frye

Williams Honors College, Honors Research Projects

Stainless steel rebar is one of the most corrosion resistant reinforcing methods for concrete structures. Stainless steel is used for its chromium content and its ability to form a passive oxide corrosion resistant layer. The presence of chloride is one of the largest attackers of this passive film and able to penetrate concrete due to its porous characteristics. This study evaluates the mechanical performance of different stainless steels relative to their changing environments. It is expected that as chloride concentration values increase, mechanical properties will decrease. This will be tested by performing tensile tests on stainless steel rebar sample that …

Development Of Cardanol-Based Epoxy Coating, Nicholas Pottschmidt

Williams Honors College, Honors Research Projects

The purpose of this project was to determine the suitability of cardanol glycidyl ether (CGE) as a substitute for trimethylolpropane triglycidyl ether (TMPGE) as the reactive diluent in epoxy coatings. CGE may be a naturally-derived alternative to TMPGE, which is a commonly-used petroleum-derived reactive diluent. Epoxy coatings were formulated with CGE replacing increasing amounts of TMPGE in the formulation. Corrosion protection provided by the coatings was evaluated with electrochemical impedance spectroscopy (EIS). Mechanical properties of the coatings (hardness, flexibility, adhesion, and impact resistance) were evaluated with applicable ASTM standards.

EIS results revealed the coating formulated with only CGE had superior …

Microwave Detection Of Surface Breaking Cracks In Metallic Structures Under Heavy Corrosion And Paint, John Robert Gallion

Masters Theses

"We live in the world of "aging infrastructures". In this environment, critical and heavily utilized infrastructure, i.e. ships, planes, bridges, etc., are operating at or beyond their designed age. Replacement is no longer an option and "retirement for cause" is the current approach to maintenance and replacement. Consequently, there is an ever-increasing demand for efficient and robust nondestructive evaluation (NDE) methods that can determine the physical health of these structures. Large structures, which are primarily made of metals, either steel or aluminum, are susceptible to high-stress cracking and corrosion. Stress-induced cracks in heavily corroded steel, used in bridges, railroads, storage …