Which frame to choose for a bike: aluminum or steel?
The bike frame is a supporting part, as all the main components are attached to it. 70% of the load falls on the frame, which is why the structure must be made of high-quality materials.
For many owners, the main criterion is the weight of the product, the less it is, the more convenient it is to manage the product. The mass directly depends on the material, so you should choose a bike based on this criterion, taking into account the pros and cons of each.
Aluminum frame, pros and cons
Aluminum frame advantages:
- low weight of the frame. Low-grade structures weigh about 2 kg, and high-quality ones weigh up to 1.5 kg;
- good performance along with low cost;
- the bike accelerates quickly on any terrain;
- do not corrode;
- withstand a lot of weight.
The disadvantages of this frame are directly opposite to the advantages of the steel frame:
- Despite their fast acceleration, they also rapidly lose momentum.
- Some models do not absorb vibration from the road, so driving can be excruciating.
- Accumulates fatigue, so breakdown can occur at any time.
- Most breakdowns are nearly impossible to fix.
Which is stronger. aluminum or steel?
Steel is much stronger than aluminum, which makes steel parts heavier in weight.
Aluminum frames are not made of pure metal, but with the addition of various elements. Often, the alloy includes impurities of chromium, zinc, titanium, manganese, iron, which improves the characteristics of parts. Most often, in the manufacture of bicycle frames, aluminum alloys of the following grades are used: 7005 and 6061.
Steel frame, pros and cons
To make steel frames, the following types are used:
- Common steel.
- Carbon steel.
- Steel alloyed with chromium and molybdenum.
Standard grade steel. It has the lowest properties, so bicycles are of low cost. Such material quickly deteriorates, the frame rusts, and the bike loses its usefulness.
Which is The Strongest Material? Carbon Fiber Vs. Aluminum Vs. Steel | Hydraulic Press Test!
Carbon steel frames have good strength properties as well as corrosion resistance. They are quite flexible, so they smooth out all the bumps on the road. Such designs are ideal for normal riding as well as for performing stunts. Carbon steel withstands heavy loads, up to 150 kg.
Alloyed steels make the structure more reliable, strong and lightweight. Most often steels for making frames are alloyed with molybdenum and chromium. Molybdenum affects the structure of the steel, making it fine-grained, thereby increasing the strength. Chromium imparts corrosion resistance.
The price for such a frame starts from 400. The high cost is the most significant drawback, which is why such bicycles are not in demand.
Advantages of steel frames:
- high indicators of strength, rigidity;
- withstand shocks;
- easy to maintain;
- unlike aluminum frames, steel frames do not accumulate fatigue. This property allows the element not to break at one moment, so the cyclist can notice the crack in time and replace the damaged part;
- repairing steel structures is quite easy, all that is needed is welding;
- bicycles are inexpensive;
- physical properties allow vibration damping when driving.
Disadvantages of a steel frame:
- tangible weight of the structure;
- structures made of ordinary steel quickly corrode;
- due to the appearance of rust, it is necessary to carefully care for the bike: paint the surface, do not leave it in rain and snow, and regularly lubricate.
Not every cyclist can choose the right frame the first time. You must have enough experience in order to navigate the materials.
Scandium Bike Frames
Really stuff. special aluminum alloy with scandium additives.
Their main advantage. low weight. They are even lighter than titanium, at a slightly lower price. Good strength and medium softness. However, the material is extremely demanding on the production technology, otherwise it will greatly lose all its positive properties.
The types of aluminum alloys we ride
There are a large number of aluminum alloys (2014, 7000, 7005T6, 7009T6, 7010T6, 6061T6, 6065, etc.), but the most commonly used grades in bicycle construction are 7005T6 and 6061T6 (analogue of the domestic AD33 alloy according to GOST 4784-97). They are also called six- or seven-thousandth series alloys.
The T6 sign in the title indicates that the material has undergone heat treatment.
For example, during the heat treatment of alloy 6061, an article made of it is heated to 530 ° C, then intensively cooled with water. Then it is artificially aged for 8 hours at a temperature of about 180 ° C. After such processing, alloy 6061 is already designated 6061-T6.
Alloy 7005 during heat treatment is cooled not with water, but with air.
Grades 7005 and 7075 are stronger than 6061 and will last longer than 6061 alloys. 6061 is more processable than 7xxx alloys. And this makes it easier to make pipes with a complex section from it and butt them, which also increases the strength of such frames. 6061 aluminum is easier to weld than 7005.
It turns out that both materials are good and you can compare them only if you know the technology of their production, and no one will tell us this)
Welding a frame made of pipes made of 2014, 7075 aluminum is generally a very complex and expensive technological process. They cannot be welded with conventional argon arc welding. During production, they can only be cast entirely. That is why these brands are practically not used in the production of bicycle frames.
Steel vs. Aluminum Frames
The 6061 aluminum frame is better suited for freeride (FR) and downhill frames. For XC hardtail bikes, the 7005 alloy is optimal. It is stronger, stiffer and more durable.
Cyclists are not very fond of aluminum frames due to their rigidity and the impossibility of welding in “any village” in contrast to conventional steel welding.
Cons of carbon:
Also carbon should be “know” all the same. Overtightening the seatpost clamp on an aluminum or steel bike will break the bolt or its thread as much as possible. On the carbon seatpost, you can get cracked.
Original and experimental materials for bicycle frames
Pros of carbon:
Carbon steel (High Ten)
This steel is already more advanced with good performance and rust resistance. It is flexible enough to dampen vibrations while riding, and the price is very affordable.
Great for heavy people up to 150 kg.
Cons of magnesium:
- Point impacts are even worse tolerated, even than with carbon;
- Has the worst running characteristics on steep climbs, with sharp accelerations, especially when power pedaling;
- They are highly susceptible to corrosion and are very afraid of aggressive environments;
- They do not tolerate strong weight loads. If you weigh more than 95-100 kg and you are a cyclist with huge backpacks, this is not your choice;
Carbon VS Aluminium VS Titanium VS Steel | The Bike Frame Material Showdown: Which Is Best?
This material is more commonly seen in suspension forks today.