|
5.7 MIL-HDBK-17: Composite Materials Handbook
Mark Vangel Mark Vangel is Chairman of the Statistics Working Group of Mil-Handbook-17, which develops and publishes statistical methods for composite materials. These materials, which can have exceptionally high ratios of strength and stiffness to weight, are of growing importance, particularly in the aerospace industry. However, strength properties of composite materials typically exhibit considerable variability across test specimens, due to the brittleness of most fibers, the brittleness of many matrices, and to processing. Statistical methods (specifically methods for tolerance limits, mixed model analysis, and quality control) are thus important to the use of these materials. Mil-Handbook-17 is an evoloving document which is intended to be used as a primary reference, both for data and for guidelines on data analysis, by composites engineers, by the Department of Defense, and by regulatory agencies. In 1999 the Working Group worked on developing statistical procedures for acceptance testing of new materials (i.e. receiving inspection) based on the mean and the mininum value for a group of specimens. Another emphasis has been on developing methods for combining lamina and laminate data using regression tolerance limits.
Date created: 7/20/2001 |