The Titanium Development Association calls titanium "the material of choice," and there are a lot of people in the bike industry who would agree. Its reputation within the industry is excellent: light weight, super strength and fatigue life, a magical ride ... and a heavy price tag, to boot. So let's find out what the physical characteristics are that give titanium such an enviable reputation.
TI'S REAL PLUS: ELONGATION AND TENSILE STRENGTH
Compared to steel and aluminum's property of No. 3, elongation, titanium is miles ahead of either material. This is the property that tells you how far something will bend before it breaks, a kind of safety factor for framebuilders. Elongation numbers for titanium are often 20 to 30 percent. For comparison, typical steels can be 10 to 15 percent - the higher strength steels go down as low as 6 percent. Aluminum typically runs in the 6 to 12 percent range. Higher strength aluminums again creep into the low range of single digits, with warning bells ringing loudly. Things without much elongation are said to be brittle. Brittle frame failure is not a good thing. The tensile strength of titanium is also excellent. The cold-worked-stress-relieved yield strength (see "Touring the Ancotech mill" to find out more on CWSR) of the 3/2.5 alloy (that's the alloy usually found in bicycle frames) is typically 100-130 KSI or more. This compares favorably with many steels we find in bicycles. Remember, too, this is achieved with fantastic elongation numbers, and at almost half the weight. And we haven't even talked about fracture toughness and endurance limit yet.
The fatigue strength is another property where titanium performs beautifully. There is not a definitive measurement of fatigue strength that will tell us how the material will last in a bicycle frame. Bicycles are subjected to forces of varying amounts in a random, cyclic fashion. As long as these loads are kept below a certain level, titanium and steel both have thresholds below which they will never fail. Almost none of the aluminum (including the metal matrix composites), magnesium and beryllium used in bicycle fabrication has a defined endurance limit.
Titanium is an exceptionally hard, durable and corrosion proof material. When built properly, it is a lifetime frame material that puts up with abuse better than any other material.
3Al/2.5V titanium alloy, or titanium alloyed with 3% Aluminum and 2.5% Vanadium. This is an ideal material to build a frame from, since it has an incredible strength to weight ratio, but is still resilient enough to withstand considerable flex without permanent damage. This is the material almost all of the highest quality titanium bike frames are made from, and is a mainstay in the aerospace industry because of its impressive properties.
According to the International Titanium Association, Titanium naturally resists corrosion. An advantage of owning a Titanium bicycle is that it will not rust. This might look specially appealing to people who stay in snow areas where the roads are fully salted in winters, which results in corrosion of metal. A titanium bicycle will help you as well as serve you longer than other metals, which could rust and decay under the same conditions. Another benefit is titanium's rust resistance is that you do not need to paint the bicycle. Apart from this, Titanium bicycles are designed as lightweight rides in that form, they tend to be flexible and better for lighter riders. It lasts for a long time. Titanium is more expensive but it has powerful corrosion resistant properties that is even better than platinum. Titanium can be guaranteed lifelong as it continues to maintain the same durability and appearance it did the day you bought it. Light weight coupled with strength makes titanium a favorite among bicyclers. Titanium actually has the "highest strength-to-weight" ratio of any metal. There are also no known health risks with Titanium. Since the metal is almost always pure, lead and other contaminants are absent in these bicycles. These traits together make titanium bicycle a smarter choice for all terrain riders.