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Studies in a number of countries have attempted to determine the national cost of corrosion. The most extensive of these studies was the one carried out in the United States in 1976 which found that the overall annual cost of metallic corrosion to the U.S. economy was $70 billion, or 4.2% of the gross national product. To get a feeling for the seriousness of this loss, we may compare it to another economic impact everyone is worried about – the importation of foreign crude oil, which cost $45 billion in 1977.
Recent years have seen an increasing use of metal prosthetic devices in the body, such as pins, plates, hip joints, pacemakers, and other implants. New alloys and better techniques of implantation have been developed, but corrosion continues to create problems. Examples include failures through broken connections in pacemakers, inflammation caused by corrosion products in the tissue around implants, and fracture of weight-bearing prosthetic devices. An example of the latter is the use of metallic hip joints, which can alleviate some of the problems of arthritic hips. The situation has improved in recent years, so that hip joints which were was at first limited to persons over 60 are now being used in younger persons, because they will last longer.
An even more significant problem is corrosion of structures, which can result in severe injuries or even loss of life. Safety is compromised by corrosion contributing to failures of bridges, aircraft, automobiles, gas pipelines etc., the whole complex of metal structures and devices that make up the modern world.
The economic consequences of corrosion affect technology. A great deal of the development of new technology is held back by corrosion problems because materials are required to withstand, in many cases simultaneously, higher temperatures, higher pressures, and more highly corrosive environments. Corrosion problems that are less difficult to solve affect solar energy systems, which require alloys to withstand hot circulating heat transfer fluids for long periods of time, and geothermal systems, which require materials to withstand highly concentrated solutions of corrosive salts at high temperatures and pressures. Another example, the drilling for oil in the sea and on land, involves overcoming such corrosion problems as sulfide stress corrosion, microbiological corrosion, and the vast array of difficulties involved in working in the highly corrosive marine environment. In many of these instances, corrosion is a limiting factor preventing the development of economically or even technologically workable systems.
International concern was aroused by the disclosure of the serious deterioration of the artistically and culturally significant gilded bronze statues in Venice, Italy. Corrosive processes will accelerate the deterioration of precious artifacts such as those in Venice by the highly polluted environments that now are prevalent in most of the countries of the world. Likewise, inside the world's museums conservators and restorers labor to protect cultural treasures against the ravages of corrosion or to remove its traces from artistically or culturally important artifacts.
