1211 Standards

The term standards has many implications. To the researcher and the technical community, it may be fundamental test methodologies and units of measure. To the manufacturer or end-product user it may be materials specifications and tests to meet requirements. Commercial standards equate to the rules and terms of information transfer among designers, manufacturers, and product users [2]. There are even fundamental differences between levels of standards: company (internal use with only internal consensus); industry (trade/project use with limited organizational consensus); government (wide usage and varying levels of consensus); fullconsensus (broadest usage and greatest consensus).

At present, there are few—national or international—full-consensus standards for testing advanced materials such as advanced ceramics. This limited ability to test on a common-denominator basis hampers further material development [2]. For example, specific areas where standardization (or consensus) are required include terminology/nomenclature, test fixtures, test specimen geometries, specimen preparation, machining procedures and allowable tolerances, test specimen alignment, optimal straining/stressing rates, metrology (temperature and strain), testing environment, and identification of fracture and failure modes. These needs are particularly acute at elevated temperatures or in aggressive environments where test equipment and measurement techniques are often being developed simultaneous with the test material. Although considerable development may be required for standards for many advanced materials, rather than adopting entirely new or unconventional methods and techniques, test methods developed originally for the room temperature characterization of conventional materials are a good starting point to develop test methodologies for advanced materials in particular.

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