The applicability of instrumented falling weight impact techniques in characterizing mechanically thermoplastic foams at relatively high strain rates is presented in this paper. In order to try simulating impact loading of foams against sharp elements, an instrumented dart having a hemispherical headstock was employed in the tests. Failure strength and toughness values were obtained from high-energy impact experiments, and the elastic modulus could be measured from both flexed plate and indentation low-energy impact tests. The results indicate a dependence of the failure strength, toughness, and the elastic modulus on the foam density, the foaming process, and the chemical composition. This influence was found to be similar to that of pure nonfoamed materials and also to that observed from low-rate compression tests. The results also indicate that the indentation low-energy impact tests were more accurate in obtaining right values of the elastic modulus than the flexed plate low-energy impact tests usually used to characterize rigid plastics. The foam indentation observed with this test configuration contributes to obtaining erroneous values of the elastic modulus if only a simple flexural analysis of plates is applied.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
ISO/DIS 6603–1, "Plastics-Determination of puncture impact behavior of rigid plastics," International organization for standarization (1997).
J. G. Williams, in "Fracture Mechanics of Polymers" (Ellis Horwood Ltd., London, 1984) p. 41.
A. J. Kinloch, G. A. Kodokian and M. B. Jamarani, J. Mater. Sci. 22 (1987) 4111.
N. J. Mills and A. M. H. Hwang, Cell. Polym. 9 (1989) 259.
P. Loveridge and N. J. Mills, ibid. 12 (1992) 393.
T. Casiraghi, G. Castiglioni and T. Ronchetti, J. Mater. Sci. 23 (1988) 459.
A. B. Mart´inez, J. Arnau, O. Santana and A. Gordillo, Inf. Tec. 5 (1994) 19.
L. B. Greszcuk, in "Impact Dynamics," edited by L. B. Greszczuk, J. A. Zukas, T. Nicholas, H. F. Swift and D. R. Curran (John Wiley & Sons, New York, 1982) p. 55.
L. Rayleigh, Phil. Mag. 11 (1906) 283.
H. Hertz and J. Reine, Ang. Math. 92 (1881) 156.
S. P. Timoshenko, in "Theory of elasticity" (McGraw-Hill, New York, 1934).
M. A. Rodr´iguez-p ´erez, O. Alonso, J. Souto and J. A. De Saja, Polym. Test. 16 (1997) 287.
S. P. Timoshenko and S. Woinowsky-krieger, in "Theory of plates and shells" (McGraw-Hill, NewYork, 1984) p. 71.
L. J. Gibson and M. F. Ashby, in "Cellular Solids: Structure and Properties" (Pergamon Press, Oxford, 1988) p. 43.
P. R. Hornsby, in "Two-Phase Polymer Systems," edited by L. A. Utracki (Carl Hanser Verlag, Munich, 1991) p. 93.
M. A. Rodr´iguez-p´erez, J. I. Velasco, D. Arenc ´on, O. Almanza and J. A. De Saja, J. Appl. Polym. Sci. (submitted, 1998).
About this article
Cite this article
Velasco, J.I., Martínez, A.B., Arencón, D. et al. Application of instrumented falling dart impact to the mechanical characterization of thermoplastic foams. Journal of Materials Science 34, 431–438 (1999). https://doi.org/10.1023/A:1004565822502
- Elastic Modulus
- Compression Test
- High Strain Rate
- Mechanical Characterization