The Brittle Fracture of Polycrystalline Zinc


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In polycrystalline materials grain boundaries provide an important contribution to the resistance to the propagation of both brittle and ductile cracks. In this paper we describe experimental measurements of brittle cracks developed within both small punch and matchstick test specimens of polycrystalline hcp zinc. These specimens were tested over the temperature range 77 to 423K. Fractography undertaken using focussed ion beam imaging provides detail of the propagation from grain to grain and across {10-12} twins of (0001) basal and {10-10} prismatic cleavage cracks. The results are discussed by comparison with the predictions from previously described 3-D geometric modelling applied to this hcp polycrystalline material.



Key Engineering Materials (Volumes 348-349)

Edited by:

J. Alfaiate, M.H. Aliabadi, M. Guagliano and L. Susmel




G. M. Hughes et al., "The Brittle Fracture of Polycrystalline Zinc", Key Engineering Materials, Vols. 348-349, pp. 41-44, 2007

Online since:

September 2007




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[4] G.M. Hughes, G.E. Smith, P.E.J. Flewitt and A.G. Crocker submitted to Proc. Roy. Soc. (London) 2006 Figure 1. Zn fracture surfaces; experiments were carried out at (a) 77K, (b) 293K and (c) 328K. Scale marker, c, applies to images (a-c). Accommodation at a grain boundary in low temperature fracture of Zn as the crack propagates from grain A to grain B is shown in (d).