Fracture mechanics test methods

Moore, D., Pavan, A., and Williams, J. 2001. Fracture Mechanics Testing Methods for Polymers, Adhesives, and Composites. Elsevier, New York. 

A further development of this procedure is fatigue crack propagation (FCP) experiments in the presence of a stress cracking environment. While in the fracture mechanics test methods described above the specimen is under constant load, in a FCP experiment the specimen is tested under cyclic loading conditions in the presence of a sensitizing medium. 

Moore DR, Pavan A, Williams JG, eds.. Fracture Mechanics Testing methods for Polymers, Adhesives and Composites, ESIS Publication 28, 2001, Elsevier. 

Davies, P., B.R.K. Blackman, and A.J. Brunner, Mode II delamination, in Fracture mechanics testing methods for polymers adhesives and composites, D.R. Moore, A. Pavan, and J.G, Williams, Editors. 2001, Elsevier Amsterdam, London, New York. p. 307-334. 

ESIS 28 Fracture Mechanics Testing Methods for Polymers Adhesives and Composites. 

It is my great pleasure to introduce the proceedings of the ESIS TC4 conference, Fracture of Polymers, Composites and Adhesives , which was held in the mountain resort of Les Diablerets, Switzerland between 15-18 September 2002. This was the third conference organised by TC4 and, as on the two previous occasions, it reflects the main activities of the committee which are focussed on developing fracture mechanics test methods for polymers, adhesive joints and composites. 

Blackman, B. R. K. and Kinloch, A. J., "Fracture Tests for Structural Adhesive Joints, in Fracture Mechanics Testing Methods for Polymers," Adhesives and Composites, A. Pavan, D. R. Moore, and J. G. Williams, Eds., Elsevier, Amsterdam, 2001, pp. 225-267. 

Use of fracture mechanics test methods for failure analysis of FRP composite elements is feasible, but to the best knowledge of the author, no examples of this have been published. The challenge here is mainly the preparation of suitable test specimens from structural elements and the creation of the starter cracks. ISO 15024 does provide some information on mode I starter crack preparation for nonstandard specimens in an informative appendix (B.8, Guidelines for wedge precracking ), and that procedure can be adapted for other specimen geometries. 

Table 8.1 Quasi-static fracture mechanics test methods for FRP composites...

Blackman BRK, Bruimer AJ, Davies P. Delamination fracmre of continuous fibre composites mixed-mode fracture [Chapter 4.3]. In Moore DR, Pavan A, Williams JG, editors. Fracture mechanics test methods for polymers, adhesives and composites. Elsevier 2001. pp. 335-59. http //dx.doi.org/10.1016/S1566-1369(01)80040-6. 

OlMoo Moore, D. R., Pavan, A., Williams, J. G. (eds.) Fracture mechanics testing methods for polymers. ESIS publication 28, Elsevier, Amsterdam, 2001. 

Some investigations [105-107] on micron-.size particle-filled composites demonstrated that fracture toughness is dramatically influenced by the particle shape, size, volimie fraction, and particle/matrix interfacial strength. Brunner et al. [108] reviewed the development of fracture mechanics test methods in determination of fracture toughness and delamination resistance of fiber-reinforced polymer composites. 

A completely different set of tests are referred to as Fracture mechanics test methods. In these tests, attempts are made to measure true material properties of the adhesive joint independent of the geometry test. Such test methodologies require careful preparation of samples so that all experimental variables are controlled. A typical parameter measured for such joints would be the adhesive fracture energy, and normally, this would be determined as a function of some parameter such as the rate or temperature of testing. 

Hale, G.E. Ramsteiner, F. (2001). J-fracture toughness of polymers at slow speed. In Fracture mechanics testing methods far polymers, adhesives and composites, Moore, D.R. Pavan, A. Williams J.G., editors, pp 123-157, Elsevier Science Ltd. and ESIS, ISBN 0 08 043689 7, The Netherlands. 

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