Tag: Steel Facts

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6 Factors to Consider When Choosing Between Aluminum and Steel

Different Kind Of Metallic Profiles

What are the important factors to consider when choosing between aluminum or steel?

  1. Durability
  2. Strength
  3. Corrosion Resistance
  4. Versatility
  5. Weight
  6. Cost

 

Aluminum and steel are some of the most utilized metals across different industries for a multitude of products and building projects. Steel is popular because of its high tensile strength, low cost, and recyclability. But don’t go calling your local stainless steel supplier right away because aluminum can still make a case for its worth.

Aluminum is the third most abundant metal in the earth’s crust. It also has the best strength-to-weight ratio and is unbeatable when it comes to the variety of its uses: automobile, motorcycle, and bicycle parts. It is also used in aircraft design and architectural moldings. Like steel (especially the stainless kind), it is also a very environmentally efficient metal which makes using either metal good for the environment.

 

  • Durability

The first and most apparent factor you are going to have to take into consideration is durability. Metals are typically known for their durability, but not all of them have the same kind of durability. The ability to withstand wear and tear, pressure, or damage varies from metal-to-metal and when it comes to steel and aluminum, there are some notable differences.

 

  • Strength

Metal Railing At The Facade Building Monochrome

Tensile strength is the name of the game when it comes to durability, and in that regard, steel is king. Tensile strength is the maximum amount of stretching or pulling a metal can withstand before it breaks or is permanently damaged. Without getting into specifics, steel and all of its sub-categories have a higher tensile strength than aluminum and its derivatives. This is by no means an indication that aluminum is a weak metal that easily breaks — steel is just a bit stronger.

 

  • Corrosion Resistance

Luckily for aluminum, tensile strength is not the only way to evaluate durability. Resistance to corrosion is also important to consider because metals become susceptible when exposed to the elements. Corrosion is a natural process that converts refined metals to a more chemically stable form (think of your oxides and sulfides).

That being said, steel is an alloy that is made up of refined metals like iron and copper, so they are pretty susceptible to rust. Despite that, the more popular derivative, stainless steel, has chromium added to its alloy formula to give it an anti-corrosion layer. This pretty much solves the corrosion problem.

Meanwhile, aluminum has an edge over steel in this regard because it does not contain steel or iron, meaning it does not rust. The thing is, rust is just one kind of corrosion that affects metals. Aluminum, when exposed to weathering and atmospheric oxygen, can oxidize and produce a layer of aluminum oxide. What’s interesting to note here is that aluminum oxide actually protects the metal from further corrosion. What this means is that the more aluminum corrodes, the more it is protected from further corrosion.

Either way, you really cannot go wrong. Both metals are competitively durable and have a good level of corrosive resistance. The important part here is knowing what kind of elements are present in the environment you are going to use the metal in before deciding which to use.

 

  • Versatility

Shiny Silver Metallic Textured Background

Versatility is where things start to favor aluminum. The “miracle metal” is well known for its malleability. This means it can be successfully de/reformed and bent into a variety of custom shapes or profiles without suffering noticeable breaks or cracks. Aluminum is also very ductile, allowing it to be stretched without breaking.

When it comes to temperature, aluminum is also the more versatile choice because it becomes harder as temperatures go lower. Steel, meanwhile, tends to become a little more brittle under cold temperatures and that affects its aforementioned tensile strength. Both metals and alloys have no problem withstanding high temperatures though and should hold up even in a fire. Just avoid touching it.

 

  • Weight

As previously stated, steel is stronger across the board, but aluminum wins the strength-to-weight ratio. This is why aluminum becomes the better choice in the production of transportation modes such as aircraft, automobiles, and locomotives. Lower weight means better fuel efficiency and faster speeds.

Steel, on the other hand, is heavy and is better for solid structures requiring stability and foundational strength. Seeing both metals incorporated in a multitude of ways isn’t an uncommon sight as products, buildings, and pretty much anything that can be built will always be better with steel and aluminum parts working together to full effect.

 

 

  • Cost

Stainless Steel Entrance Guard At Apartment Entrance

Lastly, cost should always be taken into consideration when choosing a metal to use for your respective purposes. In this regard, steel is usually less expensive, but it still depends on what kind of steel you are looking to get. Your run of the mill steel and carbon steel are less expensive than aluminum, while stainless steel is pricier. It all depends on your budget and the specific job you are going to use it for.

 

Key Takeaway

Steel and aluminum have their advantages and disadvantages, but what both have in common is that they are products of metallurgical ingenuity and are good for a number of different industrial purposes.

It all boils down to what you need to do, what your budget is, and what specific particulars you are going to be dealing with. Tailor your choice according to those, and you should be good to go.

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Stainless Steel Philippines: Types of Corrosion

Stainless Steel Philippines Types Of Corrosion

What are the different types of corrosion?

  1. General Attack Corrosion
  2. Galvanic Corrosion
  3. Localized Corrosion
  4. Environmental Cracking
  5. High-Temperature Corrosion

 

Metal and stainless steel in the Philippines are widely used as a primary material for many industries. They’re tough, readily available, and can be used for various applications. Though metals aren’t indestructible, they have one major weakness. Corrosion may be caused by many different conditions and factors, let’s take a look at a few different types of corrosion:

 

General Attack Corrosion

This is the most common type of corrosion; it is also commonly known as uniform corrosion. It is considered to be an even attack of oxidation across the surface of a metal material. This form of corrosion is usually easy to determine because it is relatively simple to replicate and reproduce its effects with consistency. Usually, causes of this form of corrosion are due to chemical exposition or from an electrochemical reaction.

From this point, general attack corrosion will render the full deterioration of the metal to the point of structural failure. As mentioned earlier, it’s the most common type of corrosion, which correlates to this type of corrosion accounting for the greatest amount of metal destruction via corrosion. Since it’s common, it isn’t difficult to prevent and predict. Oftentimes, a metal that succumbs to this type of corrosion is still manageable and even preventable.

 

Galvanic Corrosion

Galvanic Corrosion

Galvanic corrosion, often times called dissimilar metal corrosion happens when two dissimilar metals are in contact with one another and in the presence of an electrolyte. This usually happens at metal structural locations such as joints or weld spots. To know how this type of corrosion occurs involves taking a deeper look at metals from a molecular level.

Three conditions must be met in order for this type of corrosion to occur. First, the metals in contact must be electrochemically different. Second, the metals in contact must be electrically connected. Third, the metals must be exposed to an electrolyte. When these conditions are met, one metal starts giving its electrons to the other metal or it becomes an anode, while the other receives the electrons or becomes a cathode.

In Galvanic corrosion, the anode will begin to rapidly rust with the cathode will become more resistant to corrosion. A common example of this is when copper and steel are linked together and suddenly become exposed to salt water.

 

Localized Corrosion

Under localized corrosion, we have three types: pitting, crevice, and filiform corrosion. These types of corrosion target a specific area in a metal’s structure.

  • Pitting Corrosion – is one of the most difficult types of corrosion to spot. It happens when a cavity is formed in the metal. What happens in the cavity is that the exposed area experiences a loss in electrons, the anodic area then becomes more susceptible to a localized form of galvanic corrosion. This cavity will weaken the structure of the metal from within, leading to potential failure.

 

  • Crevice Corrosion – crevice corrosion is similar to pitting corrosion but it doesn’t involve any electron loss. This type of corrosion happens when a cavity, small hole, or crevice in a metal becomes exposed to a stagnant microenvironment. Because of the acidic environment or the exhaustion of oxygen in a crevice, this will lead to corrosion.

 

  • Filiform Corrosion – One of the subtlest corrosions that can slip under the guise of many, filiform corrosion is a form of corrosion that happens under any form of coating. Common instances that because filiform corrosion is when a coating breach occurs and water slips in between the metal and its coating. This form of corrosion spreads underneath paint, epoxy, and many other forms of coating to cause structural weakness.

 

Environmental Cracking

Environmental Cracking

Environmental cracking is a common form of corrosion that occurs to metals exposed to various environmental conditions. Oxidation, temperature change, and chemical exposure are a few factors that contribute to various structural damages such as stress corrosion cracking, metal embrittlement, corrosion fatigue, and hydrogen induced cracking.

 

High-Temperature Corrosion

Often caused by high-temperature oxidation and carbonization, high-temperature corrosion typically happens in vehicle’s turbochargers, diesel engines, and exhaust pipes. This happens due to the fuels used in these types of machines; during combustion, various compounds attach themselves to the metal and quickly corrode the surface. At times, even stainless steel may rust due to high-temperature corrosion.

In the Philippines, stainless steel products that are exposed to high-temperature corrosion usually don’t mean that structural integrity will be compromised. Typically, in older engines, you may notice that the exhaust side of a turbocharger will always be more rusted compared to the intake side, but it still works well.

 

Key Takeaway

Knowing the different types of corrosion can help you determine whether your metal structure, parts, or components can be saved and how they can be remedied. With this knowledge, you can somehow pinpoint the causes of corrosion and prevent them from happening. If you want high-quality stainless steel that can combat the harshest effects of corrosion, click here to learn more about One Sky Philippines.