Volume 9, Issue 4, 2000

Flexural testing of Composite Laminates for Drilling Trial Assessment

I.R. Farrow^a,*, J.Lee^b, C.D.Kong^c

                  ^a,b Department of Aerospace Engineering, Bristol University, Bristol, UK, BS8 1TR                  Tel +44 (0)117 928 7704; fax +44 (0)117 925 1154; E-mail address:ian.farrow@bristol.ac.uk

^cCollege of Engineering, Chosun University, 375 Seosuk-dong, Kwangu, Republic of Korea

*Author to whom correspondence should be addressed

(Received 4/00; accepted 7/00)

ABSTRACT

This work presents a study of flexural testing as a convenient method for ranking drilling trials of composite materials. The work includes an experimental study of drilling parameter effects on composite laminate hole quality as measured by static tension, compression and flexural open hole tests. Flexural testing and results processed in terms of the outermost 0° layer provides a consistent ranking of holes drilled with different process parameters despite only subtle changes in static notched strength for the thick composite samples tested. Specific observations from flexural tests are consistent with current drilling practices in terms of best process parameter settings and the method shows sufficient sensitivity to distinguish between the effects of drill-entry and drill-exit damage and subtle changes in lay-up.