Patent · US Expired

System for nondestructively determining composite material parameters

US5031457A · kind A · utility

28Cited by
3References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 21, 1989
Grant dateJul 16, 1991
Priority date
Expiry dateJun 21, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2291/2632
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus for nondestructively determining fiber volume fraction and resin porosity of a composite material constructed of at least two different constituent materials wherein the following parameters of the composite material to be tested are known: density, elastic moduli of the constituent materials and layup sequence. Two acoustic waves of different polarizations are propagated through the composite material and the acoustic waves propagated through the composite material are sensed and the velocity of each of the two acoustic waves, V.sub.1 and V.sub.2, are determined. The thickness of the composite material is determined. The fiber volume fraction and resin porosity of the composite material are then determined using the velocities, V.sub.1 and V.sub.2, the thickness and known parameters of density, elastic moduli of the constituent materials and layup sequence.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.