Low energy impact

Fig. 1 High re.solution X-ray refraction topography of low energy impact (5J) at CFRP epoxy laminate. Image area 2 mm X 4 mm. Horizontal resolution 0.2 mm. The image represents selectively an area of debonded fibers of vertical fiber orientation.

Fig. 2.17 Particle size (ECD) of Tego Magnan powder milled for 100 h under the low-energy impact mode with one magnet and subsequently subjected to five cycles of desorption at 300°C under 0.1 MPa pressure for -4,700 s/absorption at 300°C under 2.5 MPa for 60 min...

S. Li, R.A. Varin, O. Morozova, T. Khomenko, Controlled mechano-chemical synthesis of nanostructured ternary complex hydride Mg FeH under low-energy impact mode with and without pre-milting , J. Alloys Compd. 384 (2004) 231-248. 

The example of a label given in the figure is typical for commercially available safety glasses, e.g., for laboratory use, and shows mechanical strength (resistance against low energy impact), having a specific UV filter, and optical class 1. 

Figure 10 Visualization of low-energy impacts detected by eddy currents on a CFRP panel.

Gros, X. E. (1996), Characterization of low energy impact damage in composites, J. Reinforted Plastics Composites. March 1996. 15, 3, 267-282. 

Plastics products are most likely to fail in a brittle manner under impact conditions, both due to strain rate effects and because large forces can be generated by low energy impacts on stiff structures. A variety of impact tests are used. Usually a weight falls from a height of the order of Im to hit the test specimen with a velocity of about 5ms . This simulates the strain rates that occur when a product is dropped about a metre, but not the higher strain rates in vehicle collisions or ballistic impacts. The uses and limitations of three types of impact tests will be discussed. 

Seaver M, Aktas E, Trickey ST. Quantitative detection of low energy impact damage in a sandwich composite wing. J Intell Mater Syst Struct 2010 21(3) 297—308. http // dx.doi.org/10.1177/1045389x09347020. 

Aurrekoetxea J. Sarrionandia M. Mateos M Aretxabaleta L. (2011) Repeated low energy impact behaviour of self-reinforced polypropylene composites. Polymer testing. Vol.30, Issue. 2, pp. 216-221. 

Macromolecular modifiers are used to improve some physical properties, mainly mechanical properties of polymers. They have found wide-spread application in the reduction of basic defects of polymers in their glassy state, mainly their resistance to low-energy impact, and they are used also to modify rheological properties of polymer melts [1]. 

Moore, D.R. and Prediger, R.S. (1988) A study of low energy impact of continuous carbon-fiber- reinforced composites. Polym. Compos., 9, 330. 

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