1223astm

ASTM has implemented committees (e.g., ASTM Committee C28, Advanced Ceramics) that are in the process of identifying and addressing the more pressing standardization needs for advanced materials, surveying which needs are satisfied by existing ASTM (or other) standards and establishing liaison with other organizations to enhance the standards-setting process through collaborative arrangements. One requirement for the success of these standardization efforts is that the resulting test methods are shaped with industrial users in mind. Often research-oriented test methods are not necessarily acceptable as commercial standards. To ensure commercial usefulness, industry must participate in the standards-setting process. The ideal standardized test method should be simple to conduct, should use small, easily fabricated and prepared specimens, and should be capable of measuring simultaneously elastic properties and performance (e.g., first matrix microcracking stress, ultimate strength as well as corresponding strains).

It is useful to look at the organization of ASTM to understand the standards development process. As shown in Fig. 12.1, the oversight of the ASTM standardization process is the Committee on Standards. Below this executive committee are the technical committees, for example, Committee C28. Committee C28 is further subdivided into subcommittees, for example Subcommittee C28.07 Ceramic Matrix Composites. Finally, the technical work of the subcommittee is accomplished on the task group level, of which there are currently eight in the example of Subcommittee C28.07. It is important to note that task group leaders are free (and encouraged) to recruit any appropriate experts (members and nonmembers of ASTM) who they deem necessary to complete the work of the task group. Note that in Fig. 12.1 that the flow of standards development is from the task groups to the executive committee. Thus, the technical aspects of the standard are the driving force, with the executive committee ensuring procedural, format, and layout conformance with the norms of the society, and not necessarily technical correctness.

FIGURE 12.1 Standardization organization of ASTM.

Once a task group has developed a draft standard, it is submitted to all members of the subcommittee for ballot. Members vote and comment on the technical rigor as well as the usability (format, language, etc.) of the draft standard. Any negative ballots will stop the approval process until either the negative is dealt with (withdrawn or found nonpersuasive) or the item withdrawn from ballot. Once the draft standard has been approved on the subcommittee level, it is submitted to all members of the main committee for ballot. As in the subcommittee ballot, members vote and comment on the draft standard and any resulting negatives stop the approval process until they are resolved. Finally, after being approved at the sub and main committee levels, the draft standard is submitted for a "society review," which does not require each member of the society to vote, but instead only holds up a draft standard if a member votes negative after inquiring about the draft. Once the draft standard has passed these three levels of approval the Committee on Standards must approve that due process was followed. The ASTM standards produced by this process are described as "technically rigorous and of high quality."

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