Accession Number : ADA139300

Title :   Microscopic Study of the Influence of Impurities on Interface Bonding.

Descriptive Note : Annual technical rept. 1 Dec 82-30 Nov 83,

Corporate Author : TEXAS UNIV AT AUSTIN CENTER FOR MATERIALS SCIENCE AND ENGINEERING

Personal Author(s) : Marcus,H L

PDF Url : ADA139300

Report Date : 25 Jan 1984

Pagination or Media Count : 45

Abstract : Results are reported for two experimental areas associated with interface failure. Model layered systems, with the main emphasis on the Al-Al2O3-Graphite system, were studied for varied interface chemistry and thickness. The results show that when the interface has low resistivity fracture occurs within the graphite but when the interface resistance is high fracture occurs within the interface. This holds true for a wide range of interface chemistries and impurity doping at the interface. Introduction of an embrittling element at the interface of the low resistance interface did not change the fracture path. The second experimental area studied was the influence the interface plays on the fracture behavior of the discontinuous SiC/Al matrix composites. Both discontinuous fibers and particulate SiC dispersoids were studied. In all cases interface failure was not the dominant fracture path. The more ductile the matrix the more ductile the composite and the less interface failure. Gamma-Al2O3 was observed to be present at many of the interfaces. (Author)

Descriptors :   *Chemical bonds, *Impurities, *Composite materials, *Fracture(Mechanics), Interfaces, Aluminum, Aluminum oxides, Silicon carbides, Matrix materials, Fibers, Graphite, Thickness, Doping, Embrittlement, Ductility, Strength(Mechanics), Electrical resistance, Electrical conductivity, Microscopy, Auger electron spectroscopy

Subject Categories : Inorganic Chemistry
      Laminates and Composite Materials
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE