Aluminum is an incredible metal. It is versatile, lightweight, durable, and ductile all at the same time. If you ask any home developer, they would tell you that aluminum is a great choice over other metals for various applications. It can perform effectively and efficiently in a wide array of environments. Against another popular metal, stainless steel, aluminum displays a variety of strengths that will make you rethink your interior projects. But Can Aluminum Replace Stainless Steel?
When comparing aluminum to other metals, including steel, it weighs less by volume. Aluminum’s weight is only a third the weight of other metals, including steel, brass, and copper. According to the Aluminum Association, construction items made by aluminum are more cost-effective than steel items. When using aluminum in construction projects, you can gain a savings of up to 55 percent compared to if you use steel.
In the marine transportation industry, aluminum structures are also more cost-effective compared to steel. Aluminum hulls have a weight savings of 35 to 45 percent. If aluminum is used instead of steel to construct marine superstructures, there is a weight savings of 55 to 65 percent. Fuel and battery consumption is more cost-effective in aluminum than steel structures because lightweight vehicles use less energy. According to Drive Aluminum, electrical cars that have advanced aluminum body structures use fewer batteries than those with steel body structures, which results in a weight savings of up to 3,000 (US) dollars per unit. Compared to steel hybrid cars, aluminum hybrid cars experience fuel savings of 5 to 7 percent.
Comparing Aluminum and Stainless Steel
Both stainless steel and aluminum are widely used materials across industries, in a variety of projects and products. For instance, stainless steel is used for everything from kitchenware and cutlery, to the construction of buildings, to many of the appliances we see in our everyday life. Aluminum, on the other hand, is almost always seen in the construction of most automobiles and motorcycles, bicycles, and aircraft. It is also used a lot in architectural moldings and trims, as well as the framework for furniture items, of residential homes and commercial buildings.
While these are two useful materials, aluminum is often preferred over stainless steel, especially when it comes to choosing furniture for interior decoration and/or renovation. When you compare the strength, weight, corrosion resistance, and cost of aluminum vs steel, you will quickly see why interior developer often have a lot of faith on the many advantages of using aluminum over the good-old stainless steel.
Keep in mind these 10 differences between aluminum and stainless steel when deciding which metal to use in your next project:
1. The ratio of material strength and durability compared to weight
Aluminum is not usually as tough and sturdy as stainless steel, but in terms of specific gravity, it also weighs almost a third of that of stainless steel.
Because of its lightness, this is the main reason a lot of aircraft manufacturer choose aluminum for the frameworks.
If made entirely of steel, the weight of an aircraft will be too heavy, which leads to difficulties in engine power for it to take off from the tarmac, which also leads to higher fuel consumption.
2. Corrosion properties
Stainless steel, also known as SUS, is made up of iron, chromium, nickel, manganese, and copper. Chromium is added as an agent to provide corrosion resistance. The chromium oxide coating on the outside of stainless steel is what makes it anti-rust, if this surface layer is scratched, it can rust. There are many types of stainless steel with grading such as: SUS201, SUS304, SUS316.
The most common type of stainless steel is SUS 304 (or stainless steel 304), which is used for kitchen sinks, food processing equipment and steam pans, etc. SUS 304 is very resistant to corrosion. But for use in chemical environments, the new SUS 316 is a more reliable choice. Also, since SUS 316 is non-porous, corrosion resistance is increased.
On the other hand, aluminum is naturally highly resistant to oxidation and corrosion, mainly due to its passive oxide layer. When aluminum is oxidized, its surface will turn white, and sometimes develop holes. In some extreme acidic or basic environments, Aluminum can corrode quickly with more dire results.
Because of the difference in the anti-corrosive properties of aluminum and stainless steel, stainless steel is often used as a material for tank structures for chemicals, solutions, oil, gasoline, etc. with greater safety. Application in environments with high temperature, humidity and corrosive agents helps stainless steel objects and parts have a longer life.
3. Thermal conductivity
Aluminum has much better thermal conductivity than stainless steel. This is one of the main reasons it is used for car radiators and air conditioning units.
The wind radiators on motorbikes and on computer cooling chips, TVs, and electronic devices are commonly made of aluminum. Coils on cold and hot units of air conditioners are also usually machined from aluminum tubes.
4. Aluminum and stainless-steel prices
Aluminum price is usually cheaper than that of stainless steel. The main reason is that aluminum is a common metal, while stainless steel is an alloy created from metals and goes through many complicated steps. In order to produce stainless steel, normally it must go through six stages: melting & casting, forming, gas-heating, descaling, cutting, and finishing. Aluminum production is less complicated, consisting mostly of ore refining and Al2O3 molten electrolysis.
5. Workability
Aluminum is fairly soft and easy to cut and shape in milling and turning. This is also known as being “malleable”. Due to its abrasion resistance, stainless steel can be difficult to process. It requires more care with cutting tools and cutting modes during machining.
6. Welding
Stainless steel is relatively easy to weld, while aluminum can be tough.
7. Thermal properties
Stainless steel can be used at temperatures much higher than aluminum, which can become very soft above about 400oC.
8. Electrical conductivity
Stainless steel is a really poor conductor of electricity compared to most metals. Aluminum, on the other hand, is a much more excellent conductor of electricity. Due to its high electrical conductivity, light weight, and resistance to corrosion, high voltage power lines are often made of aluminum.
9. Material strength and sturdiness
Stainless steel is stronger than aluminum (provided weight is not a consideration). However, aluminum is more efficient, as it has a better weight-to-strength ratio.
10. Effects on food
Stainless steel reacts less with food. Aluminum can react with food which can affect color and taste. Therefore, stainless steel is often used widely for applications in kitchen utensils, food storage and mixing tank structures, confectionery dipping, food processing in factories.
What makes Aluminum stand out?
Aluminum is naturally non-corrosive. Meanwhile, stainless steel only has these properties depending on the combination. Aluminum actually can form an oxide film that naturally protects the metal from corrosion. This natural corrosion protection happens when aluminum reacts with oxygen. As a result, it forms a barrier that protects itself from various compounds, including water, or further exposure to oxygen. This natural barrier is one reason that aluminum works more effectively in some environments than carbon steel and some stainless steels. It’s important to note that stainless steel can corrode in “aggressive conditions.” Stainless steel often has to undergo painting or other treatments to protect it from corrosion.
In terms of heat conductivity, aluminum outperforms stainless steel. Any chefs working in kitchens would know that aluminum-based cookware is more efficient for cooking food than steel-based cookware. Aluminum kettles boil water more quickly than stainless kettles. This is a result of aluminum being more heat-conductive, transferring heat more quickly than steel.
Aluminum also conducts electricity quicker than stainless steel does. This high electrical conductivity, combined with aluminum’s lower melting point than that of stainless steel, means that aluminum can raise the electrical discharge level in machining five-times compared to steel.
When it comes to thermal conductivity, aluminum is four-time better than stainless steel. In terms of aluminum products and processes, aluminum’s thermal conductivity reduces cooling cycles more efficiently than stainless steel, making aluminum windows and doors more ideal for indoors ventilation for homes in hotter or colder environment. Furnishing your home with aluminum furniture will help your living space not turn into either a microwave or a freezer.
Stainless steel is not very malleable, which is why many manufacturers choose to use aluminum instead. Stainless steel is stuck with only a certain number of possible shapes and formations. Meanwhile, aluminum is more malleable (more elastic). Engineers and designers will have more creative freedom in creating the perfect interior objects for home decoration.
All in all, aluminum is a lighter, cheaper, and more versatile material for interior design than stainless steel. Therefore, when decorating and/or renovating your home, consider using aluminum-made furniture items.
