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Bob notes that corrosion is a major problem that affects many industries. Bob has spent over forty years studying and solving corrosion problems in the construction, aerospace, defense, petroleum, utility and related industries. He was also the technical editor of Corrosioneering-the On-line Corrosion Journal and maintains worldwide contacts in the fields of corrosion engineering and research. He teaches courses on corrosion control for a variety of audiences throughout the United States and abroad. His litigation experience in corrosion-related cases frequently finds causes other than corrosion for the problems encountered by clients, and this ability to identify the root cause of a problem is often very useful.

Bob states that effective corrosion control requires a thorough understanding of protective coatings, cathodic protection, corrosion inhibitors, alloy selection and heat treatment, and a variety of other factors. Bob's litigation and research experience leads him to the conclusion that ineffective corrosion control is often the result of not understanding the interdisciplinary nature of corrosion control and the interrelationships between a wide variety of factors that affect corrosion control. He states that designers frequently don't consider inspection for continuing service in their designs and this leads to major problems in many industries. It is common to have unexpected corrosion failures in systems where corrosion monitoring has been underway, but the corrosion occured in locations where monitoring was ineffective. This kind of failure of monitoring and design systems has led to major environmental degradation and worldwide negative publicity for the organizations involved. It has also cost many millions of dollars of environmental damage due to relatively small localized corrosion damage.

Bob states that corrosion is best prevented in the design stage. Bob has presented courses on design for corrosion prevention to international audiences in the petroleum, shipbuilding, and construction industries. He has also consulted for a number of manufacturers and customers who had corrosion problems that were due to improper materials selection or faulty designs. Once a product/structure is completed, then protective coatings, cathodic protection, or modifications to the design can be applied to limit the problems associated with corrosion. Another approach is to inspect and monitor the progress of corrosion. Bob notes that it is important to locate the monitoring points in the appropriate place and to select the methods of monitoring so that changes in corrosion rates will be detected.

Bob spent seven years as a faculty member in the Ocean Engineering Department at the University of Rhode Island. His research and consulting emphasized corrosion of aluminum weapon systems, fasteners used in marine environments, cathodic protection in sea water, and a number of other practical problems associated with marine corrosion. He developed a course on marine corrosion for AIChE and wrote the section on marine cathodic protection for the Metals Handbook. He has also worked on plumbing system failures and related problems. He is the author of several articles on marine cathodic protection that have appeared in Volumes 13A and 13C of the Metals Handbook. In 2009 he wrote an invited article comparing the effects of dissolved gases and salt contents on aqueous corrosion.

Bob notes that corrosion in concrete is a major problem that affects a number of industries. Bob started work on this in 1971 when he worked for the Corps of Engineers on concrete revetments for the Mississippi River. His research on corrosion in concrete has been funded by the National Science Foundation and presented at various National Association of Corrosion Engineers (NACE International), American Concrete Institute (ACI International), the Transportation Research Board, and ASTM forums. His litigation consulting includes concrete and masonry construction problems throughout the United States. Structures include buildings, pipelines, culverts, and hydraulic structures. Most problems associated with concrete construction involve improper construction practices, and it is frequently possible to identify why corrosion occurred by relating degradation patterns to structural loading, connection details, and drainage designs. Most corrosion in concrete is attributed to the presence of chloride ions, but chlorides are almost everywhere and many coastal and deicing salt structures perform quite well. It is important to identify why a structure is experiencing distress, and the chemical environment is frequently only a minor contributor to the problem. Bob has been successful in identifying the root causes of corrosion in concrete and masonry systems for a wide variety of clients. In recent years he has also been involved in analyses of cathodic protection systems sold for controlling corrosion in concrete buildings. In recent years he recommended to a client that cathodic protection could not be effective on the partially-embedded steel of the exterior walls of a major structure in a high-visibility location in a major city. He was also able to point out that cathodic protection was not working on a beach front condominium structure in Florida.

Bob's experience with atmospheric corrosion started with studies of the performance of weathering steels in a number of locations. He also was involved in litigation associated with buildings and curtain wall construction. Since that time he has spent several summers working at the NASA Kennedy Space Center, where the atmospheric corrosion test site is the most corrosive in North America.

Bob states that "chloride corrosion" is a field that is misunderstood by many so-called experts in the corrosion and construction industry. Research over the past several decades has shown that chlorides are found in most localized corrosion situations. Bob's experience related to chloride corrosion includes extensive, multiyear exposure testing in marine environments as well as litigation experience for a major supplier of a chlorine-containing product. He maintains a close relationship with a beachside corrosion test site on the Atlantic Ocean and lives on the beach. He's surrounded by corrosion associated with chloride salts. He also has experience showing that much alleged "chloride corrosion" would have occurred in the absence of chlorides, although often at a somewhat slower rate. One major problem with alleged chloride stress corrosion was actually determined to be a fatigue problem associated with inadequate inspection for manufacturing defects.

Bob notes that most coatings failures are due to improper surface preparation. It is often necessary to use sophisticated surface analysis techniques to identify the source of contamination and explain why a failure has occurred. Bob has been doing this for over thirty years and was one of the first researchers to routinely use the scanning electron microscope for contamination analysis.

Bob notes that most corrosion problems are associated with localized corrosion in pits, crevices, stress corrosion cracks, fatigue cracks, or under biofilms. The chemistry of the environment in these localized "occluded cells" is usually very different than the chemistry of the bulk environment, and this leads to accelerated localized attack. This is a major problem on alloys with limited susceptibility to corrosion, such as stainless steels, aluminum, copper and nickel alloys, but it is also a problem on carbon steel and cast irons. Solutions to localized corrosion depend on an analysis of the specific problem and can be as simple as cleaning the surface or pretreating to provide a more resistant surface. Bob has experience in localized corrosion ranging from building walls to pressure transducers on torpedoes.

Bob notes that the marine environment is one of the most widely recognized corrosive environments. Bob has experience in analyzing changes in marine corrosion and has conducted research on the effects of temperature and pressure on corrosivity and cathodic protection. He has also worked in recent years with an organization that maintains a marine atmospheric test site, which is the most corrosive in North America. He was a faculty member in an Ocean Engineering Department for several years, and has conducted multiyear exposure tests in flowing seawater and marine atmospheric environments. Clients have included government, construction, shipbuilding, and manufacturing clients worldwide.

Bob's experience with erosion-corrosion ranges from identifying it as a major problem in a building heating system to research for a major oil company. He was the founder of the National Association of Corrosion Engineers task force on erosion-corrosion in oil and gas production. Most erosion-corrosion (or flow-assisted corrosion) occurs in multiphase fluid flow. Recent attempts to model where flow-assisted corrosion is likely to occur have caused several organizations to question whether the modeling systems used for predicting multiphase fluid flow are accurate and whether or not multiphase conditions may exist in conditions where the models predict "safe" performance.

Bob's experience with aircraft corrosion dates to the 1970s when he worked on failure analysis of jet engines for the Navy's latest fighter bomber. He was able to identify that manufacturing defects associated with forging processes were the likely causes of fan blade failures that had been previously ascribed to stress corrosion cracking. This experience in failure analysis, using a multidisciplinary approach has been applied to aerospace systems for a number of clients. Starting in 2000, he advised the NASA Kennedy Space Center on corrosion of aircraft alloys and on the effectiveness of commercial products sold for cleaning aircraft. The results of this program were presented at a series of conferences sponsored by NACE International and DoD. His experience also includes a number of failure analyses associated with airborne weapons systems and jet engines. He recently identified fatigue, as opposed to corrosion, as a major source of potential equipment failure for a major aircraft component manufacturer.

Bob has extensive experience with corrosion of aluminum and copper-based alloys and has published research papers on some of these efforts. Other work in this area has been for private or government clients and has not been published. He is considered an expert on the corrosion of both aluminum and copper-based alloys and has worked on many other alloy systems to include molybedenum valves for a Navy weapons system.

Bob recently advised a client on the responsibility for corrosion control associated with a fatality due to external corrosion of a buried pipeline. He was able to advise on the devleopment of pipeline corrosion control over the past 50 years, and the development and scope of international standards and government requirements for pipeline corrosion control. Bob's first job after graduate school required him to develop a corrosion training program for utility system operators at worldwide Army bases. This got him into the cathodic protection of gas distribution systems, and he has maintained his ties to this industry for over 30 years. In 1980 he spent a summer at the Transportation Systems Center helping develop a pipeline research program for the U. S. Department of Transportation. In his capacity as technical editor of Corrosioneering-the On-line Corrosion Journal, he highlighted some of the developments in pipeline integrity monitoring and the implications for public safety. He has taught courses on cathodic protection to international audiences. He has recently inspected pipelines for corrosion damage in Mexico and advised a major oil and gas operator on coatings and cathodic protection problems in Indonesia. Other countries where he has been involved in advising on pipelines include Venezuela, Russia, Denmark, Canada, and Pakistan. The 2000 Carlsbad, New Mexico, pipeline explosion brought the problems of internal corrosion of pipelines to worldwide attention. He has followed these developments over the years and recommended changes in practice to pipeline operators. Many of the problems associated with multiphase pipelines can be applied to other systems which have similar problems.

Bob states that "uniform corrosion" is a misleading term. It is more informative to use the term "general corrosion," because variations in corrosion rate are common. They can be caused by such factors as structure geometry, orientation relative to the sun and weather patterns, operation of nearby equipment, and a variety of other factors. Bob has experience working with a wide variety of metals and alloys in a large number of industries. He places emphasis on economic solution to practical problems.

Bob states that austenitic stainless steels are the workhorses of the chemical process industries. They are also used in many other applications. Bob has worked with a variety of clients who had problems understanding which stainless steel to use for a given application. He has even developed a cathodic protection system for stainless steel fasteners used on an oceanic data buoy system.

Bob notes that aluminum is a metal that is often used because of its light weight and its strength-to-weight ratio. It is also corrosion resistant in many environments. Bob has worked with clients who specified 7000-series aluminum alloys for use in a corrosive environment and then had to live with the consequences of that unfortunate alloy selection. Another client used aluminum galvanic anodes for tugboats in a freshwater lake. The anodes didn't corrode, which meant that the hulls of the vessels they were supposed to protect did corrode. Understanding aluminum alloys, their surface treatment and finishing processes, and where they can be used in corrosive environments is one of Bob's areas of expertise.

Bob states that most corrosion of cans is due to improper cleaning/preservation of the steel surface prior to tin plating. Other problems occur when the environment is such that the tin is cathodic to the steel substrate instead of the anodic state associated with deaerated organic acids--the ideal environment for tin-plated steel. Identifying the root cause of corrosion failures is one of Bob's specialties.

Bob notes that there are numerous corrosion detection devices on the market, and he has experience with many of them. One group of devices is sold with the intention of being used for corrosion monitoring/corrosion control. Most of these devices are electrochemical in nature. Unfortunately, most of these devices are oversold and cannot deliver, in a real environment, the precision and reliability that the customer seeks. Bob has worked with these devices and has experience on when they can, and cannot, work. He also understands corrosion inspection using nondestructive inspection.

Bob notes that galvanic protection can be either cathodic protection--the use of "galvanic" or "sacrificial" anodes to protect a structure--or it can be the use of an anodic coating (aluminum, zinc, cadmium, or tin) to protect an underlying substrate metal. Bob has worked on all of these systems.

Bob's experience with corrosion of iron alloys includes carbon steel (structural members, reinforcing steel, etc.), weathering steel, and stainless steel. He knows all of these materials and has worked and published on all of them.

Bob served as the adviser on a recently completed study by NASA for the Army on the corrosion inhibition properties of a number of proprietary chemicals sold to the aircraft industry for rinsing aircraft. After a multi-year test several of the products were found effective while others were found to result in more corrosion than no rinsing or with weekly rinsing with seawater. The results of this study (with the identity of the proprietary products masked) have been published in several venues.

Bob notes that cavitation is a major cause of premature failure on piping systems, pumps, and other high-velocity liquid handling systems. As the founding chair of the NACE task group on erosion-corrosion in oil and gas production, Bob became involved in this form of failure in the 1980s and has remained cognizant of efforts to control this problem in the oil and gas production, power plant, and other industries.

Bob has been considered an expert on the costs of corrosion since his work on the costs of corrosion for the Department of Defense in the 1970s. He is currently under contract to the Department of Defense to develop an assessment of the costs of corrosion on worldwide DoD facilities.

Bob notes that corrosion coupons are frequently used to monitor the effectiveness of corrosion control programs in piping systems, storage tanks, process vessels, and similar equipment. Bob's work has shown the limitations of simple weight-loss exposure tests. He has also worked with NASA using the scanning electron microscope and automated image analysis to determine the effectiveness of corrosion control on corrosion coupons exposed to various environments. His emphasis is on the limitations of various techniques so that the client understands what coupons can, and cannot, determine or indicate.

Bob notes that corrosion monitoring can involve coupon exposure, nondestructive inspection, or electrochemical techniques for determining instantaneous corrosion rates. He states that, unfortunately some of these electrochemical techniques are oversold. While they may perform well in the laboratory, the limitations of using them in the field are often misunderstood. In an interesting field demonstration, Bob and his technician were able to show that the corrosion rate at a remote location went up every morning at 2 a.m. and down at 6 a.m. Once this pattern was detected it was easy to correct the problem. Unfortunately, most corrosion monitoring techniques used by industry could not detect these short-term changes.

Bob notes that most technical people understand some of the reasons why seawater is corrosive. He states that unfortunately, fresh water is often similarly corrosive, and the reasons for this are often misunderstood. Bob has worked with clients on analyzing why corrosion rates are higher than expected in a number of circumstances. This has included recommendations for utility systems, industrial processing organizations, and attorneys involved in litigation due to misunderstood causes of accelerated deterioration.

Bob notes that intergranular corrosion is a well-documented problem in both stainless steels and in aluminum alloys, but it also can occur in carbon steels and most other alloys. Bob has provided an understanding of how to control intergranular corrosion to the petroleum refining, aerospace, and military hardware industries. He has emphasized the importance of manufacturing processes and machining on how this occurs and how it can be minimized.

Bob notes that there are many sources of hydrogen in steel, but the most common causes are improper bakeout of electroplated machinery parts and hydrogen entry "poisons" such as hydrogen sulfide, a common contaminant in crude oil and natural gas. Bob has conducted failure analyses on hydrogen embrittled high-strength steels and has supplied technicians and professionals for inspection of hydgrogen blistering of low-strength steels in storage tanks and other vessels.

Bob notes that there are many kinds of metal alloys. The corrosion patterns associated with these many alloys depend on the alloy chemistry; manufacturing method; machining, welding and surface preparation methods; and a variety of other factors. Bob has experience explaining corrosion patterns for many alloys based on all of the above factors. His work has been for military, manufacturing, legal, and other clients.

Bob notes that anodized aluminum is the most commonly used passivated metal, although carbon steel is also passivated with phosphoric acid and other treatments. (That is why carbon steel rifle barrels are bluish black instead of silver or corroded.) Bob has worked on metal passivation processes for controlling corrosion and wear, preparation of substrates for subsequent organic coatings, and the failure of large storage tanks used for storing "passivating" acids.

Most of Bob's work on nonferrous metal corrosion has been concerned with aluminum in aerospace, weapons, and building applications. He was also able to identify the cause of premature corrosion of copper piping in a major building and has worked on a variety of other alloys. He recently attended a meeting where many engineers were complaining about magnesium corrosion and not understanding the reasons why magnesium was used for complex castings on machinery.

Bob notes that sacrificial protection is usually a form of cathodic protection involving the use of galvanic anodes made of magnesium, zinc, or aluminum alloys to control, usually, corrosion on carbon steel or similar alloys. Sacrificial protection is also used with galvanized steel and a limited number of non-zinc coatings. Bob is familiar with the reasons why sacrificial coatings cannot be used on high-strength steel fasteners and why it is sometimes possible (although unusual) to experience polarity reversal wherein the metal normally acting as an anode in a galvanic couple becomes the cathode. He teaches on this subject to international audience.

Bob states that most people have a general feeling that saltwater (or seawater) corrosion can be expected to be faster than corrosion in the absence of salt. While this is generally true, the increased corrosion rate for immersion in saltwater is only about 50% compared to corrosion in freshwater. Corrosion in concentrated brines is frequently slower than in fresh water. Most reasons for these complicated interactions were explained in the 1930s and 1940s, but many people still don't understand the principles. This is why the petroleum industry spent hundreds of millions of dollars on retrofitting offshore structures that were inadequately designed. Bob's research since the 1970s has emphasized marine corrosion. He has consulted for a variety of industries and for litigation clients on saltwater corrosion, why it happens, and what can be done about it.

Bob notes that carbon steel is the most commonly used alloy group in the world. While it has many desirable properties, corrosion resistance is usually unacceptable without some means of corrosion control. Bob has experience with weathering steels and carbon steel structures of all types. His work has concentrated on design practice, cathodic protection, and other means of corrosion control. His legal clients often rely on his experience to determine if corrosion is the cause of the problem or merely a side effect.

Bob states that the corrosion of water pipelines is the most expensive cost of corrosion in the United States economy. Bob has worked on this problem since the 1970s, when he was employed by the Corps of Engineers to develop a worldwide corrosion control program for utility systems. He is still working for the government on this problem, although most of the technical solutions have been know for decades and most problems can be solved using existing technology.

Atmospheric galvanic corrosion occurs only near the junction between two or more metals. Bob has completed a project for a major supplier of construction materials where the client was concerned about potential liability due to increased corrosion of aluminum due to the presence of the clients product. Recommendations included methods for assessing whether this alleged problem did, in fact, exist, and methods for testing to determine the presence or absence of deleterious effects.

Most metal structures are made from carbon steel. Bob has experience in all methods of controlling corrosion on carbon steel structures. He also works on the interaction of mechanical properties and forming history with corrosion patterns. This has become a major area of concern in natural gas pipelines and other structures.

Bob is the author of the most recent article in the Metals Handbook, Volume 13--Corrosion, on cathodic protection. He has over 30 years of experience in teaching, evaluating, and troubleshooting cathodic protection systems for buried utilities, marine structures, pipelines, and other applications.

He has consulted for several chemical companies on corrosion problems in their manufacturing facilities. Industries involved include nuclear chemicals and pharmaceuticals.

He has consulted on copper structures as diverse as the Statue of Liberty in New York harbor and plumbing in housing and similar structures. He has also consulted on the effects of copper ions on the corrosion of other metals.

He was involved in the failure analysis investigations into the primary causes of compressor blade failures on a new jet engine for a major engine manufacturer. The government management suspected stress corrosion cracking. In conjunction with fractographic evidence from the manufacuturer and a major government laboratory they were able to convince the manufacturer and the customer that the faiures were due to undetected forging laps being missed by the nondestructive inspection process at one of the two primiary suppliers of these compressor blades.

He also participated in a quality audit on the reasons for numerous failures of engines on an engine in long term production.

Most recently he was a consultant to a major manufacturer of engines on the rehabilitation of used parts. He was able to point out that corrosion damage, a concern of the customer, was less likely to produce critical stress concentrations, than the existing fretting damage on the same parts. This cause this manufacturer, and their major customer, to re-evaluate their acceptance/rejection criteria for one of the most commonly used aircraft engines in commercial production.

Most cases of corrosion failure analysis require an understanding of the complete system involved in the equipment or stucture having the corrosion problem. He has used state-of-the art analytical equipment to identify trace elements leading to stress corrosion failures. He has also brought an understanding of structural mechanics into many investigations where the root cause of the failure was a mechanical or structural problem that caused corrosion. In many cases, the complete analysis of a corrosion problem requires an on-site inspection of the system having the problem. This has allowed him to identify root causes not recognized by the owner of the structure/equipment in question.

This work has been done for many equipment and structure owners. It has often been associated with litigation and, in most cases, has resulted in out-of-court settlements of the corrosion-related disputes.

Most cavitation erosion damage occurs in locations where piping systems change direction or undergo other geometry/pressure changes. He has consulted with major pipeline operators and chemical companies on locating nondestructive inspection points in approriate locations to detect this damage. He is also the founding chair of the NACE International committee on erosion corrosion in oil and gas production. This committee was a result of his efforts working for a major oil company.

Bob has been involved in identifying fatigue failures and identifying the root cause of the failures for over 30 years. Fatigue problems have ranged from aircraft engines to thermally-induced debonding of insulation on exterior building panels of a school in Pennsylvania. While most fatigue failures occur on rapidly-loaded rotating equipment, it is also possible to identify fatigue mechanisms associated with much slower loading patterns. Many fatigue failures are misidentified as corrosion problems, and he has often been able to identify the structural/mechanical causes of failure where other consultants/experts with more limited backgrounds have concentrated on chemical contamination which was proven to be of only secondary importantance. He was one of the first users of scanning electron microscopes with attached X-ray spectrometers to apply fractographic analysis to industrial fatigue failures. This equipment, which has largely replaced replicas used in conjunction with transmission electron microscopes, was new when he first started using it. It has now become so common that he taught undergraduate failure analysis courses where the students were expected, by their senior undergraduate year, to already understand the use, and limitations, of this equipment.

Bob started studying the transport of hydrogen in electroslag-remelted steel in 1975. This work led to an understanding of the fact that, at that time, two major groups of researchers were working on hydrogen embrittlement, stress corrosion cracking, etc. with little or no understanding of the developments underway by the other groups. One group concentrated on high-strength metals, including steel but also including other metals such as titanium, in manufactured equipment such as machinery, aircraft, etc. The other group was concerned with hydrogen sulfide effects in oil and gas production and refiniing. He has been able to translate his understanding of progress with the manufactured equipment group to the oil and gas industry. He was also able to apply his understanding of corrosion processes to "surface trapping" and other misunderstandings in the primarily metallurgically-oriented studies of the manufacturing groups. In recent years he has used his understanding of hydrogen effects, and the developing international standards on how to deal with them, to problems ranging from electroplated coatings on high-strength fasteners to the advisability of using certain alloys in refineries in eastern Europe.

Bob has extensive experience designing laboratory and field testing protocols to determine the suitability of specific materials for various environments. He is also familiar with many of the international standards associated with corrosion testing.

It is common to modify an international standard to more closely approximate the mechanical or chemical environment of the product in question. It is also necessary to -identify the limitations of various testing methods. As one example, corrosion testing is often required using salt-spray testing, a method of corrosion testing developed for use in testing the quality of electroplated coating techniques. It is unfortunate that many organizations have used these short-term quality-control tests in attempts to predict long-term performance in atmospheric and other corrosive environments.