Accession Number : ADA219864


Title :   Development of Damped Metal Matrix Composites for Advanced Structural Applications


Descriptive Note : Technical rept.


Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK APPLIED RESEARCH LAB


Personal Author(s) : Updike, Clark A. ; Bhagat, Ram B.


Full Text : http://www.dtic.mil/get-tr-doc/pdf?AD=ADA219864


Report Date : APR 1990


Pagination or Media Count : 100


Abstract : The development of damped metal matrix composite structures for advanced applications has been investigated by the use of two different approaches: 1) the development of metal matrix composites with high intrinsic damping compared to that of the matrix material, and 2) the development of coated metal matrix composites with high structural damping compared to that of the composite substrates. The two different approaches are analyzed in terms of their potential for improved damping and feasibility for structural applications. Damping was measured by the transverse vibration of free-free beams using the bandwidth technique by a laser vibrometer under ambient conditions. The damping measurements were made over a wide range of frequencies (.7 kHz to 25.6 kHz) at low strain amplitudes 10 to the -10 power to 10 to the - 7 power). Materials investigated for their tensile stiffness, strength, and damping performance include mechanically alloyed (MA) Aluminum-Magnesium, SiC(p) /Aluminum-Copper (MA), SiC(p)/AL, AL2O3(p)/AL, SiC(W)/AL, planar random Gr/AL, unidirectional Gr/AL and unidirectional SiC(Nicalon)/AL composites. The effects of coatings of high damping metals (nitinol and incramute) on 6061-T6 AL and AL2O3(p)/AL substrates have also been studied. The AL-Mg (MA), SiC(p)/AL (MA), SiC(W)/AL and th AL2O3(p)/AL composites show no significant improvement in damping compared with that of the 6061-T6 AL.


Descriptors :   *COMPOSITE MATERIALS , FREQUENCY , METALS , MEASUREMENT , STIFFNESS , DAMPING , MATRIX MATERIALS , COATINGS , NICKEL ALLOYS , TRANSVERSE , TITANIUM ALLOYS , SILICON CARBIDES , BANDWIDTH , RANGE(EXTREMES) , PARTICULATES , SUBSTRATES , METAL MATRIX COMPOSITES , TENSILE PROPERTIES , VIBRATION , STRUCTURAL PROPERTIES , POWDERS


Subject Categories : LAMINATES AND COMPOSITE MATERIALS


Distribution Statement : APPROVED FOR PUBLIC RELEASE