Carbon Forks, Strength? Tricks?

http://www.dragonplate.com/sections/technology.asp

Carbon fiber is extremely strong. It is typical in engineering to measure the benefit of a material in terms of strength to weight ratio and stiffness to weight ratio, particularly in structural design, where added weight may translate into increased lifecycle costs or unsatisfactory performance. The stiffness of a material is measured by its modulus of elasticity. The modulus of carbon fiber is typically 20 msi (138 Gpa) and its ultimate tensile strength is typically 500 ksi (3.5 Gpa). High stiffness and strength carbon fiber materials are also available through specialized heat treatment processes with much higher values. Compare this with 2024-T3 Aluminum, which has a modulus of only 10 msi and ultimate tensile strength of 65 ksi, and 4130 Steel, which has a modulus of 30 msi and ultimate tensile strength of 125 ksi.

Pros and Cons

Carbon fiber reinforced composites have several highly desirable traits that can be exploited in the design of advanced materials and systems. The two most common uses for carbon fiber are in applications where high strength to weight and high stiffness to weight are desirable. These include aerospace, military structures, robotics, wind turbines, manufacturing fixtures, sports equipment, and many others. High toughness can be accomplished when combined with other materials. Certain applications also exploit carbon fiber's electrical conductivity, as well as high thermal conductivity in the case of specialized carbon fiber. Finally, in addition to the basic mechanical properties, carbon fiber creates a unique and beautiful surface finish. Although carbon fiber has many significant benefits over other materials, there are also tradeoffs one must weigh against. First, solid carbon fiber will not yield. Under load carbon fiber bends but will not remain permanently deformed. Instead, once the ultimate strength of the material is exceeded, carbon fiber will fail suddenly and catastrophically. In the design process it is critical that the engineer understand and account for this behavior, particularly in terms of design safety factors. Carbon fiber composites are also significantly more expensive than traditional materials. Working with carbon fiber requires a high skill level and many intricate processes to produce high quality building materials (for example, solid carbon sheets, sandwich laminates, tubes, etc). Very high skill level and specialized tooling and machinery are required to create custom-fabricated, highly optimized parts and assemblies.