Accession Number : ADA260970


Title :   Smart Structural Composites with Piezoelectric Micro-Constituents


Descriptive Note : Final rept. Sep 89-Dec 92,


Corporate Author : NEBRASKA UNIV LINCOLN DEPT OF MECHANICAL ENGINEERING


Personal Author(s) : Shaikh, Nisar


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a260970.pdf


Report Date : Dec 1992


Pagination or Media Count : 17


Abstract : The research culminated into the feasibility of smart structural composite materials, in which the microstructure is modified with the introduction of a piezoelectric constituent. Greater success was achieved in the sensing aspect of smart properties, enabling the material to have an inherent property of health monitoring. By sensing and quantifying elastic strain, the material can monitor its dynamic state (vibration), degradation and damage. In actuation, the material is readily suitable for active vibration control and manipulative damping. One out-growth of the results was an active fibrous sensor, which offers a readily viable alternative to a passive fiber-optic sensor as it is marred with breakage problems. A new concept of piezoelectric emission, analogous to acoustic emission, emerged which imparts the material ability to sense stress waves. This ability can be used to locate the regions of delamination and local fractures through fabrication to operational life of structure. Techniques were developed for deposition of thin piezoelectric (ZnO) film on carbon and metal fibers. Sensing and actuation properties were imparted into carbon fiber composites. The results demonstrated self-sensing of strain and damage measurement in beam and shell elements. The concept is ready for technological advancement and application. Smart materials, Structural materials, Carbon fiber composites.


Descriptors :   *COMPOSITE MATERIALS , *CARBON FIBERS , *PIEZOELECTRIC MATERIALS , FIBER OPTICS , OPTICS , VIBRATION , MICROSTRUCTURE , STRUCTURES , DAMPING , METAL FIBERS , STRESS WAVES , DELAMINATION , ACTUATION , ACOUSTIC EMISSIONS , MONITORS , DEPOSITION , FABRICATION , FILMS , DEGRADATION , MONITORING , DYNAMICS , STRUCTURAL PROPERTIES


Subject Categories : Laminates and Composite Materials
      Electricity and Magnetism


Distribution Statement : APPROVED FOR PUBLIC RELEASE