Yes they are by quite a bit Yes they are by quite a bit.
The aluminum door is lighter and less expensive than steel door.
Aluminium is lighter than steel and much more durable
The human bone is lighter than aluminum and stronger than steel
Aluminum would be lighter weight than stainless steel.
They are lighter than the old Steel ones, but not as light as aluminum/composite ones.
Aluminum is lighter than steel, so the overall weight of the vehicle can reduced. Also aluminum doesn't rust.
It's strong enough, lighter than steel and cheaper than carbon fiber and titanium.
Aluminum is easier and cheaper to mass produce than is steel. If you recycle aluminum, you get more money for aluminum than for steel only because manufacturers have for decades focused on aluminum as the cheaper way to manufacture so many things. Aluminum is lighter in weight; is more easily bent into desired shapes; can be easily separated from other metals (chemical process); and is easily shipped to manufacturing plants. As one example, in the earlier days, airplanes contained steel and were heavier, cost more in fuel, etc. Now, all airplanes are made of aluminum shells, are lighter in weight, use less fuel because it is lighter in weight, and all of the aluminum can be recycled. Same with automobiles.
I would suggest that Aluminum is preferable. It is lighter than steel, which can result in a higher performance vehicle (faster acceleration, better braking, improved fuel economy). Furthermore, unlike steel, aluminum will not rust. Aluminum is also easier to recycle. Aluminum cars have a stiffer feel- giving them a sportier feel, and absorb impact about 1.5 times as well as steel, making them safer. The downside, of course, is the high cost of aluminum compared to steel.
Livestock trailers are a common sight on most of America’s highways. They are generally used to haul horses or cattle and range in size from small (10 – 12 feet long) to very large (40 feet long). Traditionally, livestock trailers have been made of steel. However, aluminum trailers are becoming increasingly common. As more trailer manufacturers offer aluminum products, a frequent question is: Which is the better material for a livestock trailer? As with most other comparisons, there are advantages and disadvantages to both materials. Steel trailers are sturdy, but heavy. That heaviness works both as an advantage and a disadvantage. One advantage is that a relatively heavy trailer is more resistant to damage on impact in the case of an accident or the potential damage from many stamping hooves. The disadvantage of weight is that bigger vehicles are needed to pull steel trailers than would be needed with aluminum. When talking about an average 20 foot trailer, it might be the difference between using a three-quarter ton pick- up versus a one-ton or greater vehicle. Also, unless meticulously maintained, steel trailers will rust. Aluminum trailers are far lighter than steel. Most of these types of trailers do have steel frames, but the substitution of aluminum for steel for interior and exterior panels greatly reduces the overall weight of the trailer. Because less weight is being hauled, it costs less to pull an aluminum trailer. Aluminum doesn’t rust, but riveted joints are not as flexible as steel. If the primary use requires going into a pasture to load livestock, the aluminum trailer is more likely to pop rivets or crack than a steel trailer. Initial purchase price of a livestock trailer is usually a very important consideration. On average, a new aluminum trailer may cost twice as much as a new steel trailer. While this fact might indicate that steel would be the better choice, it depends on the trailer’s intended use. For someone hauling cattle or horses many highway miles several days a week, the initial higher investment for an aluminum trailer might be offset by the savings in gas economy and choice of hauling vehicle. In the end, the answer to the question “Which is better?” depends on intended use and, of course, budget.
Actually for rockets aluminum or titanium alloys are typically better than steel as they are lighter in weight for similar strength in the mode of use.
Aluminum is used on aircraft instead of steel. This is because the density of aluminum is about 1/3 that of steel (meaning it is lighter). Aluminum is also more ductile than steel, allowing for it to bend or elastically deform without damaging the material.