Specialty Materials, Inc.
Boron is an attractive reinforcement for lightweight bicycle frames because the resulting composite combines superior tensile, compressive and flexural strengths, high modulus, and low density in one system. Room temperature compression strengths of 450 ksi for 50v/o reinforcement in epoxy have been reported. Since this is nearly twice the tensile strength, designs are never limited by compression properties.
Hy-Bor® has been used successfully in a number of structural applications. One such application in the sporting goods area is tubing for high performance bicycle frames which are light-weight, strong and stiff, shock absorbing, resilient, and resistant to corrosion. Aluminum, titanium and graphite-epoxy are all used currently, but of the three, graphite-epoxy leads in overall performance. When Hy-Bor® is included, the result is a frame with all of the advantages of graphiteepoxy coupled with reduced weight. An all-graphite 54 cm frame such as the Calfee Tetra weighs 2.5 pounds while a similar sized Hy-Bor® containing frame such as the Calfee Dragonfly weighs only 2 pounds. One-half or 0.25 pounds of this improvement occurs because of the strength and stiffening enhancement associated with the addition of boron.