Fracture behavior particle size

Figure 8.32 shows the effect of filler type and concentration on the mode of fracture. Several factors are responsible for the behavior. CaT (calcium terephthalate) fillers have good adhesion to the matrix and have an elongated shape. CaCOs (1) and (2) are both untreated fillers of smaller particle sizes (2.2 and 4.1 (dm, respectively). CaCO (3) is a stearate coated filler (better dispersion, but poor adhesion to matrix) with a particle size of 6.1 im. The mode of fracture depends on filler concentration, the degree of adhesion to the matrix, and particle size. 

By contrast with brittle resins where is independent of concentration, in pseudo-ductile one these two variables are related — when the concentration of the toughening agent decreases the elastomeric particle size must be reduced. In other words, in the latter systems it is the distance between the elastomeric particles that seems to control the fracture mechanism. Again, there are resins showing intermediate behavior between these two limits. 

Zun Zunjarrao, S. C., Singh, R. P. Characterization of the fracture behavior of epoxy reinforced with nanometer and micrometer sized aluminum particles. Compos. Sci. Technol. 66 (2006) 2296-2305. 

Elastomer Particle Size, Impact Strength, and Fracture Behavior... 

In this chapter, the fracture of WPCs as particle-filled polymer composites was elaborated. The characterization of particulate polymer composites fracture behavior and the influencing factors such as particle size as well as orientation, temperature, and loading were discussed. The fracture observation using special setup was described and the diverse numerical methods to analyze the fracture of such composites were reviewed. Finally the finite element simulation of the fracture for WPG specimen with real geometrical model was conducted and the agreement of results compared to the experimental ones was demonstrated. 

Arakawa, K. Mada, T. Takahashi, J. Todo, M. Ooka, S., Effect of Rubber Particle Size on the Impact Tensile Fracture Behavior of MBS Resin with a Bimodal Particle Size Distribution. J. Mater. Sci. 2007,42,8700-8706. 

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