Modified Mircodebonding Test for Direct Fiber/Matrix Bond Strength Determination in Fiber Composites
SourceThis paper describes a test method for determining the in situ fiber/matrix bond strength of composites. In a sequence of steps, a compressive load is applied to individual fibers oriented normal to a polished surface, and the interface is observed microscopically between loading steps, until debonding occurs. The direct result of a test is the force to produce debonding of a particular fiber. The data are reduced to a nominal interfacial shear strength through a finite-element analysis using a simplified model of the fiber, surrounding matrix, and uniform composite properties beyond the matrix. Bond strength results for a variety of composites range from 23 MPa for E-glass/polyester to 86 MPa for T300/5208 graphite/epoxy. The results are consistent with data available from other test methods.