What is Stainless Steel? How is it made?

Below is an overview of how stainless steel is manufactured, from mines to manufacturers.

But how does stainless steel move from a pile of scrap and refined minerals to its final form and application?

Most stainless steels production begin in a similar manner before the process begins. This process determines the exact composition of the steel alloy, as well as its many properties.

Therefore, to understand how stainless steel is manufactured, we must first dive into its composition.

Step 1: Melt

The production of stainless steel begins with melting scrap and additives in an electric arc furnace (EAF). EAF uses high power electrodes to heat the metal for hours to produce a fluent molten mixture.

Step 2: Remove carbon content

 

Carbon helps increase the hardness and strength of iron. However, too much carbon can cause problems such as carbide precipitation during welding.

Calibration and reduction of carbon content to appropriate levels are essential before melting molten stainless steel.

There are two ways the foundry controls the carbon content.

The first is due to argon oxygen decarburization (AOD). Injecting an argon gas mixture into the molten steel can reduce the carbon content by minimizing the loss of other essential elements.

Step 3: Tuning

After reducing carbon, the final equilibrium and homogenization of temperature and chemistry occur. This ensures that the metal meets the requirements of the desired grade and that the steel composition is consistent throughout the batch. You can get the best quality stainless steel from the duplex stainless steel pipe manufacturer.

Step 4: Moulding or casting

Once the molten steel is created, the foundry needs to create the primitive shapes used to cool and process the steel. Brass tube compression fittings suppliers supply you the high-quality stainless steel.

The following steps are the most common.

Hot rolling

Performed at temperatures above the recrystallization temperature of the steel, this step helps to establish the approximate physical dimensions of the steel. Precise temperature control throughout the process keeps the steel soft enough to operate without structural changes.

Cold rolling

Often used when precision is required, cold rolling occurs below the recrystallization temperature of steel. This process gives a more attractive and uniform finish.

However, it can also deform the structure of the steel and often requires heat treatment to recrystallize the steel to its original microstructure.

Annealing

After rolling, most steels undergo an annealing process. This includes a controlled heating and cooling cycle. These cycles help soften the steel and relieve internal stresses.

The exact temperature and time involved depend on the quality of the steel, and the rate of heating and cooling affects the final product.

Scale removal or pickles

As steel is processed through various steps, scale often accumulates on the surface.

This accumulation is simply unattractive. It can also affect the stain resistance, durability and weldability of steel.

Scale removal process remove these stains using an acid or by controlled heating and cooling in an oxygen-free environment.

Cut

Once the steel is machined and ready, the batch is cut to meet the ordering requirements.

The most common methods are mechanical methods such as guillotine knives, circular knives, cutting with high-speed blades, or punching with dies.

Sophistication

Stainless steel is available in a variety of finishes, from matte to mirrors. Common techniques include acid or sand etching, sandblasting, band polishing, band polishing, and band polishing.