What is the most significant factor regarding filler in composite for increased strength?

The most significant factor regarding filler in a composite for increased strength is the high concentration of filler particles. A higher concentration of filler enhances the mechanical properties of the composite material by improving its stiffness and strength. This is because the filler particles contribute to load-bearing capacity, and more particles in the mix provide more points of contact and interaction, which leads to better distribution of stress throughout the material.

When the filler concentration is elevated, it can also reduce the amount of resin needed to bind the particles, thereby decreasing the risk of internal weaknesses that can occur within the resin. This results in a composite that not only has greater overall strength but also improved resistance to wear and deformation.

In contrast, lower concentrations or improper particle sizes might not yield the same benefits. While particle size can influence certain characteristics, such as the smoothness of the final product or how well it can be packed into a cavity, the overall strength of the composite is primarily driven by how much filler is present in relation to the matrix material.