Carbon fiber is a lighter and stronger material to use and would theoretically be an ideal material to use for a football helmet. The problem is that carbon fiber has poor impact resistance.
The University and Oregon University worked on a project to make a complete uniform out of carbon fiber. Article below.
http://www.carbonfiberguru.com/2010/01/23/oregons-carbon-fiber-footbal-helmets/
Fiberglass is generally stronger than polycarbonate in terms of impact resistance and durability. However, polycarbonate is known for its higher resistance to shattering and flexibility, making it a popular choice for applications where impact resistance and flexibility are important.
A plastic with special coating that is 250 times stronger than glass and 30 times stronger than acrylic.
Polycarbonate is considered one of the strongest types of clear plastic for sheets, known for its high impact resistance and durability. It is often used as a substitute for glass due to its strength and clarity.
Lenses made from polycarbonate, the same type of plastic used for the space shuttle windshield, are about 50 times stronger than other lens materials.
High-index lenses are an alternative choice to standard, plastic eyeglass lenses. Although high-index lenses are more expensive than plastic lenses, they can reduce the thickness and weight of an eyeglass lens, particularly for individuals with a strong prescription. High-index lenses are able to bend light to a stronger degree than a lens with a lower index, therefore the higher the index of the lens the less material needed to achieve a given prescription. High index lenses are categorized according to how strongly they bend light. The higher the index, 1.53 to 1.74 for high-index lenses, the better the lens is at bending light. High index lenses are 20 percent to 65 percent thinner than standard plastic lenses. In general, the stronger the prescription, the greater the difference in thickness between standard plastic and high-index plastic. A reduction in lens thickness and weight will occur in high-index lenses for prescriptions stronger than +2.00 or -2.50. Weaker prescriptions are not thinner than standard lenses when made with high-index materials. Polycarbonate lenses offer the same aesthetic benefits as high-index lenses, but polycarbonate lenses scratch easier, are difficult to coat or tint and are more likely to create distortions in colors and vision.
You could try a flexi or sports frame with polycarbonate lenses. Polycarbonate is 12 times stronger than regular lens plastic and will stand up to almost eventhing that is thrown at it. Some sports frames have head straps on them to keep them in plcae when playing sports.
It is better to wear contact lenses for sport but if you are unable to, or do not want to, wear contacts, make sure that you buy Polycarbonate lenses for your glasses. Polycarbonate is 12 times stronger than regular plastic and will not break or shatter if you take a fall.
The smaller the gage the thicker the material; therefore, for the same material, 14 gage is stronger.
Auto glass is made out of a strong yet flexible polycarbonate. This is stronger than normal glass and will resist scratches and crack easier than the regular glass can.
steel
b. Choosing a material that will show warning before it fails apex
plastic