There are multiple different materials humans use to facilitate their lives. One of the most commonly available and used materials in this world is an alloy made of carbon and iron called steel. Stainless steel, in particular, is a well-appreciated material.
An important aspect of using any material is fabricating it first. The process of stainless steel fabrication is complex and requires a range of process parameters to be considered. In this article, we will discuss different fabrication methods for stainless steel.
Metal fabrication mainly involves different techniques that change the shape and form of your stainless steel. It involves cutting, bending, and other forming techniques to transform your raw material into desired structures.
Stainless Steel Categories.
Before understanding fabrication processes, we will discuss the different categories of stainless steels available in the market. These steels include austenitic, ferritic, and martensitic stainless steel. Let’s discuss them briefly:
This category contains high amounts of chromium and nickel. This makes it more stable against chemical and corrosive environmental forces than the other categories discussed below. These steels also have good flexibility and formability.
These steels are magnetic in nature. They contain lesser nickel, and so are less expensive.
These steels exhibit high strength and are preferred for load-bearing and structural applications.
Other types of stainless steel are less commonly known:
- Duplex steels contain similar compositions of ferrite and austenite phases. You get a balance of properties from both phases, like corrosion resistance and strength.
- Precipitation-hardened steels are thermally treated to improve their strength further. Examples include 17-4PH stainless steel, where the PH indicates precipitation hardening. These steels are used for high-end applications like aerospace and defense applications.
Further classifying these alloys, each category above is divided into different grades. Each type of alloy we have discussed above has different grades. And each grade has a different chemical composition, making them suitable for different applications.
Stainless Steels That Are Easy to Fabricate From.
All the steel types discussed above are suitable for fabrication. However, some steel types are most easy to fabricate than others.
- Austenitic steels are most commonly used for fabrication processes. They have good formability, are easy to weld, and have high corrosion resistance. These properties are due to the high amounts of chromium and nickel in these steels.
- Ferritic steels usually undergo a cold-forming process for hardening. Since these steels are less expensive than austenitic steels, manufacturers will sometimes opt for ferritic steels for steel fabrication if these steels’ properties are suitable for your application.
- Martensitic steels are very hard because they contain high amounts of carbon. Using this type of stainless steel for fabrication is difficult because it can experience cracking.
What Processes Are Involved in Steel Fabrication?
Different processes are used for steel fabrication. These processes include cutting, forming, welding, and finishing. We will discuss each of these processes in detail.
Different metal cutting processes shape stainless steel to our requirements. Common techniques include laser, plasma, and waterjet cutting.
- Laser Cutting: This technique uses a laser to melt stainless steel and vaporize it to create a neat cut. It is a relatively slow process suitable for cutting thin and intricate shapes in stainless steel.
- Plasma Arc Cutting: A high-temperature plasma arc is used to melt the stainless steel and cut it to the desired shape here. This technique is suitable for cutting thicker samples of stainless steel. A drawback of this technique is that the cuts produced may need to be more precise.
- Waterjet Cutting: A high-pressure water jet and abrasive material are used to cut your stainless steel sample in waterjet cutting. You can use this process to cut thick samples with precision. However, it is a time-consuming process.
A range of forming processes are available to shape your stainless steel samples as you desire. The most commonly used forming processes include rolling, bending, drawing, and spinning.
- Rolling: In this process, you pass your stainless steel sample through multiple rollers placed in series. As the sample passes through the rollers, the cross-sectional area of the sample is reduced. This process is suitable for making cylindrical shapes.
- Bending: you use a bending machine for stainless steel. As the sample passes through the machine, high force is applied to bend the sample into your desired shape. This process is suitable for creating complex shapes using stainless steel sheets and plates.
- Drawing: There are two types of drawing processes: simple drawing and deep drawing.
- In the simple drawing process, you pull your stainless steel rod through a special die having the same shape as the final shape you want.
- In the deep drawing, you pull your stainless steel rod through a series of dies to create a cup shape. You can make spherical and cylindrical shapes with this process having a smooth finish.
- Hydroforming: Hydroforming is an advanced deep drawing technique available in the market. In this process, we surround our sample with a fluid like oil or water in a rubber die and push an attached hydraulic piston to apply force and shape our stainless steel sample.
- Spinning: In spinning, you rotate a sheet of stainless steel on a lathe. A tool is then used to shape this rotating sheet as required. You can create curved shapes using this process.
The most commonly used welding processes for stainless steel include Gas Tungsten Arc Welding, Gas Metal Arc Welding, Sheet Metal Arc Welding, Flux Cored Arc Welding, and Plasma Arc Welding.
Austenitic stainless steels are most commonly used for these welding processes. They are forgiving of the process and less prone to cracking. In contrast, martensitic steels are not preferred for welding as the sample can easily crack because of inbuilt stresses.
After you’ve shaped your stainless steel sample as required, you can use different processes to improve the surface finish of your steel.
You can grind your sample using an abrasive material to smoothen its surface and remove rough edges. You can also use a polishing compound to make the surface of your sample shiny and mirror-like. You can brush the sample with a wire brush to create a patterned or matte surface finish.
Additionally, you can use methods like sandblasting to create rough textures on your steel sample. In this method, you blast an abrasive material onto your sample with high speed and pressure to create a rough texture.
Why Opt for Stainless Steel Fabrication?
The advantages of getting your projects fabricated with stainless steel include the following.
This material has a high strength-to-weight ratio, and it can bear high loads without breaking or changing shape.
2.High Corrosion Resistance
Stainless steel is stable in acidic, marine, chloride, and sulfide-containing environments. This opens up a variety of applications that many other metals can’t have.
Stainless Steel is a material that can bear high temperatures and pressures. It can also withstand wear and tear, making them much more durable than other metals.
4.Easy to Maintain Hygiene
You can easily clean stainless steel as compared to other metals. You can also easily sanitize and use them for manufacturing medical devices or equipment.
Stainless steels are visually appealing, relatively smooth, and shiny. You can use stainless steel for decorative and aesthetic applications.
Stainless steel can be fabricated into many shapes and forms and used for different applications and industries.
The Use-Cases of Stainless Steel
Some common applications of this material include:
1.Oil and Gas Industry
Stainless steel is used in the oil and gas industry to make pipes deep below sea level. This is because it can bear the high pressure experienced at depths. It’s suitable for this application as it shows high resistance to corrosion in acidic, hydrogen, and sulfide-containing environments.
Turbine blades experience high heat and pressure and must be able to remain functional under these conditions. So, stainless steel is suitable for making turbine blades as it is resistant to extreme conditions like high heat.
Stainless steel is used in the paper industry to make equipment like bulk digesters for pulp products. This is because it is stable enough to prevent rust accumulation.
As this material is easy to clean and stable against rust, it is used for making food processing equipment.
This material shows excellent corrosion resistance in marine environments. So it is used for making pumps, propellers, and other equipment commonly used at sea.
These alloys can be used for making different parts of defense equipment, like weapons and aircraft. They are resistant to corrosive forces and have a high-strength-to-weight ratio, making them lightweight and durable.
You can easily make medical devices, such as surgical instruments and implants, with this material. It has high corrosion resistance and is also easy to clean, sterilize, and sanitize, making it suitable for surgical equipment like blades for creating incisions.
Limitations of Stainless Steel Fabrication
There are some drawbacks associated with stainless steel fabrication. These include:
Stainless steel is relatively expensive as compared to other common metals. The expense also makes its fabrication process more costly.
Stainless steel is very hard, so it is difficult to machine it. High amounts of cutting forces, special equipment, and techniques are required to fabricate stainless steel, which also adds to the cost.
3.Difficulty to Weld
Most steel forms, except authentic, are difficult to weld. They can experience distortion and cracking during welding, which decreases fabrication accuracy.
Stainless steel is not easy to polish or finish and requires special finishing techniques. Surface imperfections like scratches are more visible on stainless steel than on other materials.
5.Varying Magnetic Properties.
Using magnetic grades of stainless steel in electronic devices is impossible because they will cause interference.
Stainless steel has many different types and grades, with each suiting a different application. Its fabrication processes include cutting, forming, welding, and finishing. You require special tools designed for these processes to ensure fabrication accuracy.
However, stainless steel requires high accuracy and special fabrication processes as it is a very hard and costly material. If you’re facing difficulties finding a suitable manufacturer for your stainless steel needs, please contact us to put your mind to rest!