Frequently asked questions about steel

This month we want to answer the most frequently asked questions about Steel, what is steel, what are its properties, etc.

This is a continuation of our Questions Series. Last time we covered commonly asked questions about CNC machining (stay tuned for part 2 of that).

One of the most frequently asked questions about steel; What is steel and how is it made?

When Iron is alloyed with carbon and other elements it is called steel. The resultant alloy has applications as the main component of buildings, infrastructure, tools, ships, automobiles, machines, various appliances, and weapons. The uses are myriad because of steels high tensile strength and relatively low cost.

Who discovered it?

The earliest examples of steel have been discovered in Turkey and date back to 1800BC. The modern production of steel dates back to Sir Henry Bessemer of England who discovered a method of production we high volume and low cost.

What is the difference between Iron and Steel?

Iron is a naturally occurring element found in nature within Iron Ore. Iron is the main component of Steel, which is an alloy of Iron with the main addition of Steel. Steel is stronger than Iron, with better tension and compression properties.

What are the properties of steel?

• Steel has high Tensile Strength
• It is malleable – allowing it to be easily shaped
• Durability – allowing the steel to withstand external forces.
• Conductivity – it is good at conducting heat and electricity, useful for cookware and wiring.
• Lustre – steel has an attractive, silvery appearance.
• Rust Resistance – the addition of various elements in varying percentages can give steel in the form of stainless steel it’s high corrosion resistance.

Which is stronger, Steel or Titanium?

When alloyed with other metals such as aluminum or vanadium, titanium alloy is stronger than many types of steel. In terms of sheer strength, the best titanium alloys beat low to medium grade stainless steels. However, the highest grade of stainless steel is stronger than titanium alloys.

What are the 4 types of steel?

Carbon Steel

Carbon steels contain Iron, Carbon, and other alloying elements such as Manganese, Silicon, and Copper.

Alloy Steel

Alloy steels contain common alloy metals in varying proportions, which makes this type of steel suitable for specific applications.

Stainless Steel

Although stainless steels comprise of several metal alloys, they usually contain 10-20 percent chromium, making it the primary alloying element. Compared to the other forms of steel, stainless steels are approximately 200 times more resistant to rusting, especially the types that contain at least 11 percent chromium. You can read more about stainless steel here.

Tool Steel

This type of steel is alloyed at very high temperatures and often contains hard metals like tungsten, cobalt, molybdenum, and vanadium. Since they are not only heat resistant but also durable, tool steels are often used for cutting and drilling equipment.

What is the strongest grade?

Type 440 – which is a higher grade of cutlery steel which has a higher percentage of carbon, has much better edge retention when properly heat-treated. It can be hardened to approximately Rockwell 58 hardness, making it one of the hardest stainless steels

Why isn’t steel termed as a metal?

One of the most frequently asked questions about steel is why isn’t steel classed as metal? Steel, being an alloy and therefore not a pure element, is not technically a metal but a variation on one instead. It’s partially composed of a metal, iron, but because it also has non-metal carbon in its chemical make-up, it’s not a pure metal.

Which is the most used type?

304 Stainless Steel or Type 304 the most common grade; the classic 18/8 (18% chromium, 8% nickel) stainless steel. Outside of the US, it is commonly known as “A2 stainless steel”, in accordance with ISO 3506 (not to be confused with A2 tool steel)

Is steel a sustainable material?

Steel is a uniquely sustainable material because once it is made it can be used, as steel, forever. Steel is infinitely recycled, so the investment in making steel is never wasted and can be capitalized on by future generations.

Some interesting facts about steel

• While iron is a fairly strong material on its own, steel can be 1000 times stronger than iron.
• Rusting of steel slows down or even stops entirely when an electrical current is passing through steel. This is known as Cathodic Protection and is used for pipelines, ships, and steel in concrete.
• Steel is the most recycled material in North America – close to 69% of it is recycled annually, which is more than plastic, paper, aluminum, and glass combined.
• Steel was first used for skyscrapers in the year 1883.
• It takes more than the wood of 40 trees to make a wood-framed home – a steel-framed home uses 8 recycled cars.
• The first steel automobile was made in the year 1918
• 600 steel or tin cans are recycled every second.
• 83,000 tons of steel was used to make the Golden Gate Bridge.
• The amount of energy necessary to produce a tonne of steel has been cut in half over the last 30 years.
• In 2018, the world crude steel production totaled a whopping 1,808.6 million tonnes. That’s equivalent to the weight of about 180,249 Eiffel Towers.
• You are likely surrounded by steel at the moment. A typical household appliance is made up of 65% of steel products.
• Steel is in your electronics too! Of all the materials that make up an average computer, about 25% of it is steel.
• The first major mass demand for steel came from railroad companies. Many industries soon followed in demanding steel for their needs. Steel was first used in mass production to construct railroad tracks.

We hope you enjoyed reading this article and we hope we’ve answered the most frequently asked questions about steel, if you have a question then go ahead and comment and we’ll do our best to answer it.

Here are some of the top eight Questions and Answers on Stainless Steel!

As experts in the field of stainless steel, we are often asked questions about this metal and its many properties, attributes and applications.

Read on to learn from our top Questions and Answers on Stainless Steel.

1. What is stainless steel?

Stainless steel is an alloy which means that it consists of different materials. When steel has a chromium content of more than 10.5% it is considered to be ‘stainless’.

When this chromium is combined with oxygen it forms a thin, sealed, fixed-adhering, chromic-oxide layer – the so-called passive layer. It is this passive layer that give stainless steel its distinctive corrosion resistance. While not truly stainless, even the most basic stainless steel alloys have an ability to withstand the elements and maintain their shine.

The variety of alloying elements that make up different grades of stainless steels is what allows it to have a range of properties and subsequently be so versatile with many applications.

One of the important developments in the last 10 years is the emergence of highly-alloyed grades of stainless steel. ‘Super-austenitic’, ‘super-ferritic’ and ‘super-duplex’ grades have been developed to be used in the most demanding conditions.

2. What are the five types of stainless steel?

•  1. Ferritic:Ferritic steels have high chromium level and low carbon content which gives it good ductility as well as resistance to corrosion and stress corrosion cracking.
•  2. Austenitic:Austenitic steels are the most widely used grade of stainless steel and contain high levels of chromium and nickel, but low levels of carbon. They have very good formability and resistance to corrosion.
•  3. Martensitic: Martensitic stainless steels have added carbon, meaning they can be hardened and strengthened by heat treatment which gives them improved toughness, weldability and corrosion resistance.
•  4. Duplex: Duplex stainless steels are the most recent addition to the stainless steel family. They get their name from having approximately equal proportions of ferritic and austenitic phases. This chemical composition gives the metal better strength, weight saving, greater corrosion resistance and a better price stability.
•  5. Precipitation Hardening (PH); PH stainless steel is created through the addition of copper, molybdenum, aluminium and/or titanium. It can therefore be heat-treated which generates incredible tensile and yield strengths – much more than other grades of stainless steel.

3. What is the effect of temperature on stainless steel?

Higher temperatures accelerate rates of corrosion whereas lower temperatures require increased strength. The right choice of stainless steel is crucial to protect it against corrosion.

4. Which type of stainless steel is strongest?

Higher strength is provided by austenitic, duplex, martensitic and PH steels are usually considered the ‘strongest’. However, the environment it is in can greatly affect a metals performance.

5. Which types of stainless steel can be welded?

Austenitic steels are thought to be the most weldable, however duplex steels can also be welded if handled with care. Ferritic steels can be welded but it needs to be done in thin sections.

6. What are the applications of stainless steel in heavy industries?

How does one metal get to be used in so many applications! From the humble teaspoon, to the inner workings of a MRI machine, to underground pipe in the depths of the ocean, all the way to the lofty heights of the Chrysler Building, stainless steel is everywhere you look! Within heavy industries, the applications include:

•  – Piping systems
•  – Separators
•  – Scrubbers
•  – Pumps
•  – Manifolds
•  – Heat exchangers
•  – Flowlines
•  – Storage tanks
•  – Oil rigs
•  – Deep sea drilling

7. What industries are stainless steel used in?

•  – Architecture and Construction
•  – Automotive and Transportation
•  – Medical
•  – Energy and Heavy Industries
•  – Food and Catering

8. How can you choose the right stainless steel for your project?

To ensure the best match of properties, a suitable design and manufacturing process, it is important to consider the following requirements:

•  – What is the corrosive environment of the project?
•  – What is the temperature of the operation? For example, high temperatures will accelerate corrosion rates and therefore indicate a higher grade of stainless steel whereas low temperatures will require a tough austenitic steel.
•  – What strength is required from the material?
•  – What welding will be carried out? Austenitic steels are generally more weldable than the other types. Ferritic steels are weldable in thin sections. Duplex steels require more care than austenitic steels but are now regarded as fully weldable. Martensitic and PH grades are less weldable.
•  – What product form is required? – Not all grades are available in all product forms, so you need to choose the right grade for the product you need.
•  – What is the required life cycle of the stainless steel?