Nondestructive proof loading of honeycomb panels

摘要

Techniques for testing whether a bond strength between a faceskin of a panel and a core of the panel exceeds a threshold value are disclosed. The testing includes: adhering a first surface of a sacrificial layer to a pull stub of a flatwise tensile (FWT) test apparatus by way of a first adhesive interface; adhering the second surface of the sacrificial layer to the panel faceskin by way of a second adhesive interface; operating the FWT test apparatus so as to gradually increase a FWT load on the faceskin; terminating the test upon the first to occur of separation of any one or more of the first adhesive interface, the second adhesive interface, the sacrificial layer and separation of the faceskin from the core; and determining that the bond strength exceeds the threshold value when separation of the faceskin from the core is not the first to occur.

主权项

1. A method comprising:
testing whether a bond strength between a faceskin of a panel and a core of the panel exceeds a threshold value, the testing including: adhering a first surface of a sacrificial layer to a pull stub of a flatwise tensile (FWT) test apparatus by way of a first adhesive interface, the sacrificial layer including a second surface opposite to the first surface; adhering the second surface of the sacrificial layer to the panel faceskin by way of a second adhesive interface; operating the FWT test apparatus so as to gradually increase a FWT load on the faceskin; terminating the test upon the first to occur of either: condition (i), separation of any one or more of the first adhesive interface, the second adhesive interface and the sacrificial layer; or condition (ii), separation of the faceskin from the core; and determining that the bond strength exceeds the threshold value when condition (i) is the first to occur, wherein
the bond strength is expected to exceed a specified maximal FWT load; andthe sacrificial layer is configured such that condition (i) occurs only at a tensile load that is greater than the threshold value and less than the maximal FWT load.