When mixed as part of a body filler or resin, these small particles serve a number of purposes for composite laminates.

  • Fillers are used to reinforce strength or fill gaps in targeted areas, like fabric weave, butt joints, and the surface of core materials.
  • Fillers are used to improve surfacing characteristics, like sanding.
  • Fillers can be added to resin to prevent run-off or sagging in vertical applications.

Click on an image below to get more detailed product information and pricing.

  • Talc

    Cost-Effective Filler for Sanding
    5 star rating
    Talc is a component in most body fillers, and is often added for fairing and smoothing the finish of fiberglass...
  • Glass Microspheres

    Lightweight, Sandable Filler for Surface Layers
    5 star rating
    When blended with resin, these hollow glass spheres make a lightweight, sandable filler, perfect for filling in...
  • Thixotropic Silica

    Prevent Sags on Vertical Surfaces
    4 star rating
    A white, free-flowing powder, Thixotropic Silica is a thickening agent primarily added to resin to prevent run-off...
  • 1/4" Chopped Glass Fibers

    Build Strength for Resin Systems
    5 star rating
    These longer glass fibers are used to increase tensile and compressive properties of any resin, and even other...
  • 1/16 Inch Milled Glass Fibers

    Short Fibers with High-Strength Results
    5 star rating
    Mix this milled glass with any resin, body filler, or casting material to increase strength, bulk, and dimensional...
  • 1/32 Inch Milled Glass Fibers

    Small Fibers for High-Strength Parts
    This milled glass fiber features smaller 16 micron fibers when compared to our 1 ⁄ 16 " mill... 
  • 1/4" Chopped Graphite Fibers

    Localize Strength for High-Performance Parts
    5 star rating
    Our chopped carbon fiber is commonly compounded with resins to create an easily molded composite material that is...
  • Kevlar® Pulp

    Reinforce High-Impact Areas
    5 star rating
    Reinforce High-Impact Areas Kevlar ® Pulp is the lightest of the fillers and highly abrasion res... 

Fillers should be handled carefully due to their especially small size. When mixing, take special measures to avoid "dust" and direct contact with skin and eyes. When storing, fillers should be sealed tightly against moisture, heat, and general contamination.

Fillers play an important role in composite materials by enhancing their properties, modifying their characteristics, and providing cost-effective solutions. Here are some common fillers used in composite materials:

  1. Glass Microspheres: Glass microspheres, also known as glass bubbles, are hollow microscopic spheres made of glass. They are lightweight and have a low density, which helps to reduce the weight of the composite while maintaining its strength. Glass microspheres can improve the dimensional stability, thermal insulation, and acoustic properties of the composite.
  2. Talc: Talc is a mineral filler that is widely used in composites for its excellent reinforcing and lubricating properties. It improves the stiffness, dimensional stability, and heat resistance of the composite. Talc can also enhance the surface finish and reduce shrinkage during curing.
  3. Kevlar Pulp: Kevlar Pulp is the lightest of the fillers. It adds high abrasion and impact resistance. Kevlar Pulp can improve mechanical strength, thermal stability, barrier properties, and flame resistance of the composite.
  4. Thixotropic Silica: Thixotropic Silica, sometimes referred to as the brand name Cab-o-sil, can provide reinforcement to composite materials by improving their mechanical properties. When added to a composite matrix, the high surface area and fine particle size of thixotropic silica allow for better dispersion and bonding within the matrix. This results in increased strength, stiffness, and resistance to deformation in the final composite. These are just a few examples of fillers used in composite materials. The choice of filler depends on the desired properties, performance requirements, and cost considerations of the composite. Fillers can be selected to tailor specific characteristics of the composite, such as strength, weight, thermal properties, or surface finish. It is important to consider the compatibility and dispersion of the filler within the matrix material to ensure optimal performance and uniformity in the final composite product.
  5. Chopped Graphite Fibers: Chopped Graphite Fibers as fillers offer a range of benefits, including improved mechanical properties, electrical conductivity, thermal conductivity, and wear resistance. Their lightweight nature makes them particularly attractive in weight-sensitive applications. However, it is important to consider the dispersion, alignment, and concentration of the fibers within the composite to achieve optimal performance.
  6. Chopped Glass Fibers: Chopped Glass Fibers as fillers provide composite materials with enhanced strength, stiffness, impact resistance, and dimensional stability. Glass fibers are electrically insulating, making them suitable for applications where electrical conductivity is undesirable. Glass fibers are also resistant to corrosion, making chopped glass fiber-filled composites suitable for applications in harsh environments or where exposure to chemicals is a concern. Their cost-effectiveness and versatility make them widely used in various industries where composite materials are employed.
  7. Milled Glass Fibers: Milled Glass Fibers provide composite materials with enhanced mechanical properties, dimensional stability, and chemical resistance. Their fine particle size and good dispersion characteristics make them versatile fillers for a wide range of composite applications.

These are just a few examples of fillers used in composite materials. The choice of filler depends on the desired properties, performance requirements, and cost considerations of the composite. Fillers can be selected to tailor specific characteristics of the composite, such as strength, weight, thermal properties, electrical conductivity, chemical resistance, or surface finish. It is important to consider the compatibility and dispersion of the filler within the matrix material to ensure optimal performance and uniformity in the final composite product.

You can place your order on our website or, if you have any questions, call 1.800.838.8984 | 8 a.m. - 5 p.m. EST Mon-Fri.

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