In every bicycle, there is a frame. This frame of the bicycle is known to be the most important part of a road bike. The frame of a bike can alter the overall performance of the bike, depending on which metal or alloy is used. For example, if Titanium is used, it will make the frame stronger, but not necessarily faster. This is when alloys come in. Alloys are a mixture of two or more metals. For this project, I chose to research how to build a lighter and more affordable bicycle frame. The metals that I chose to research are arguably the most efficient metals in each category; Aluminum, and titanium. With all the good things that come with these metals, there are still some drawbacks and those drawbacks, and those drawbacks relate to, in my case, economic reasons, and Environmental reasons.
At least 30 years ago, aluminum was introduced as a material for road bike frames. According to Big Shark, aluminum is the most popular and most used material in road bikes worldwide. But before the aluminum reaches the bikes, it is a metal in the rocks of Africa, North and South America, and France. Aluminum is not found on its own in nature. Other elements, for example, oxygen, and hydrogen, combine with aluminum to form ionic compounds. These compounds are present to a greater or lesser extent in almost all rocks, plants, and animals.School EB states that aluminum can either be found in rocks or clay. However, it is more economical to extract the aluminum from the rocks. This is because of experience, and it also has to be put through a lot of machines in order to be completely isolated.Aluminum is used in many things on a regular day, such as aluminum foil, most utensils, and many electronic components states School EB. Aluminum is a very light metal, which means that on bikes, it can impact the bike to be much faster than bikes made out of steel for example. According to Live Science, aluminum’s melting point is about 660.32 degrees Celsius. To give some perspective, steel’s melting point is around 1370 degrees Celsius. This shows that aluminum’s melting point is much under the melting point of steel, and that can make for much easier reshaping and makes for one of the easiest frames to make. Aluminum’s boiling point is around 2,519 degrees Celsius. This is much under steel’s boiling point at 2750 degrees Celsius. This again, can make for easier shaping and cheap frame making. Pure aluminum is not strong enough to be the frame of a road bike, so it is usually alloyed with other metals like zinc and magnesium. Also, to increase stiffness, the diameter of the tube of the bike frame is increased, and that can last, without aluminum being alloyed, but the lifetime would be decreased from 4-6 to 2-5 years.Aluminum is resistant to corrosion and can absorb shock very well, which can result in very smooth rides on the roads of the cities.
Although those pros can be very overwhelming, there still are some cons, which can sometimes result in dangerous rides. The main con is its lifetime. On average, according to London Cyclist, the lifetime of an aluminum framed bike, can range from 4-6 years lifetime. Also, aluminum bikes are usually very hard on the body, and according to London Cyclist, should only be used by professionals. Eventually, when getting closer to the end of the bike’s lifetime, small cracks will start to form on the bike, and if not noticed and had action taken against it, it could snap and cause serious injury to the rider, even in a minor crash.
The next of the two materials that I am considering is titanium. Introduced before aluminum, titanium is one of the strongest metals that are used in road bikes. When being searched for, titanium is mostly found in many minerals in Africa, and South America. Titanium can be used in many things in the regular day, such as laptop computers, and watches. According to Live Science, titanium’s melting point is about 1668 degrees Celsius. To give some perspective, steel’s melting point is around 1370 degrees Celsius. This shows that aluminum’s melting point is over the melting point of steel, and that can make for harder but more precise reshaping. Titanium’s boiling point is around 3287 degrees Celsius. This is much over steel’s boiling point at 2750 degrees Celsius. This again, can make for harder shaping, but more precise frame making. According to Big Shark, the titanium alloys are half as stiff as steel but is also half as dense. This means that the strongest titanium alloys can be compared and rivaled to the strongest steels. Very hard titanium frames need larger-diameter frame tubes than comparable steel frames, like aluminum, but not nearly as wide of a diameter is needed as aluminum. Titanium is quite corrosion resistant, and very light frames are made and can be made for riders that are heavier.
On the other hand, there still are some major downsides to titanium being used in road bikes. The main con of titanium is how hard it is to make. Titanium will bond to mostly anything especially oxygen given that it’s most common compound is titanium dioxide. Because of this, the welding cannot be exposed to oxygen, or the titanium will bond, states London Cyclist. In addition to this, titanium is harsh on tools used to manufacture it and requires a very expensive titanium welding rod. It must be joined carefully in a controlled environment, so because of this titanium frames are very expensive to produce, which explains how expensive it is to buy a titanium frame or a titanium framed bike.
In conclusion, I think that I would use an aluminum alloyed frame as supposed to a titanium frame. Titanium may be strong, and light, but given my criteria in more affordable, light, and is good in economic and environmental conditions, aluminum tops titanium in those categories. Aluminum is lighter than titanium, and if mixed with zinc or magnesium, the frame would be as strong if not stronger than titanium frames. This means that it would be a very strong, as well as light frame which means that it will be a faster and smoother ride on the roads. Titanium is one of the most expensive bicycle frames, and that is by a lot, because of it’s hard welding process. As well as that, aluminum has a lot of history to it, and it is the most common material bike frame material for a reason.
Arthurs-Brennan, Michelle. “What is Your Bike Frame Made Of? Bike Frame Materials and Their Properties.” London Cyclist. 5, Dec. 2013. http://www.londoncyclist.co.uk/bike-made/ Accessed 14 Feb 2018
“Which Frame Material is Best?” Big Shark. https://bigshark.com/articles/which-frame-material-is-the-best-pg531.htm Accessed 14 Feb 2018
“Frame and Fork Materials” City Bikes. https://citybikes.com/articles/road-bike-materials-pg57.htm Accessed 14, Feb 2018
Pappas, Stephanie “Facts About Titanium” Live Science, 3 Oct 2017. https://www.livescience.com/29103-titanium.html Accessed 14, Feb 2018
Pappas, Stephanie “Facts About Aluminum” Live Science, 28 Sept 2017. https://www.livescience.com/29103-titanium.html Accessed 14, Feb 2018
“Aluminum.” Britannica School, Encyclopædia Britannica, 6 Feb. 2018. school.eb.com/levels/middle/article/aluminum/272824. Accessed 14 Feb. 2018.