annealing-heat-treating-furnace

Heat treatment processes are necessary for various operations for glass and metals. Among these processes, the most commonly used is annealing, which helps test the material and strengthen its durability. This process also makes the material more pliable, making it easier to forge into the shape you need. 

You can also use different annealing methods, but the most efficient way involves heat treatment furnaces. Read this guide to learn how to anneal using a lab furnace.

What is Annealing?


The annealing process alters a material's physical properties by exposing it to high temperatures and allowing it to cool slowly. Sometimes, annealing can also change chemical properties, improving the material's elasticity and making it easier to use.

Metal fabricators and other businesses typically use this heat treatment method to mold different types of materials into new products across the automotive, aerospace, construction, and other similar industries.

The Annealing Process


The annealing process follows three steps: recovery, recrystallization, and grain growth.

1. Recovery Stage

In the recovery stage, heat treatment equipment raises the temperature of a material. They also heat the substance and recover its physical properties, which include thermal expansion, internal energy, and electrical conductivity.

This step aims to soften the metal into a workable state and relieve its internal stresses, which can cause cracks and other mechanical complications.

2. Recrystallization Stage

The second stage focuses on maintaining the temperature of the material above its recrystallization point but below melting temperature. This step usually applies to cold-worked metal to help gain nucleation and cause new grains to form without any pre-existing tension.

Recrystallization also helps remove the effects of heavy plastic deformation on highly shaped, cold-form metal parts. 

3. Grain Growth Stage

After the recrystallization stage, the material cools at a specific rate to cause new grains to develop while the recrystallized grains grow in size. The cooling rate is important because it controls the growth of the grains.

Completing these three steps will give the material more flexibility and less hardness. Occasionally, a subsequent process may be necessary to change the material's mechanical properties. 

How to Perform Annealing Using a Heat Treatment Furnace


These days, most lab furnaces used for heat treatment can perform a specific function. This functionality simplifies the process since you'll only need to set the heating and cooling temperatures before leaving the object inside. However, this will only work efficiently if you know the proper temperatures for the substances you're annealing. 

When using an annealing furnace, it's usually best to talk to your metal supplier to note the recommended temperatures, the methods you can use, and potential complications when working with different steel alloys. 

For example, alloys need annealing temperatures anywhere from 300°C to 410°C. And depending on the type of alloy you're using, heating times can also range from half an hour up to three hours long. You'll also need to consider the size of the material and its cooling rates.  

Why Use Lab Furnaces for Annealing?


When it comes to annealing, lab furnaces are more efficient than other equipment. Here are a few advantages of annealing furnaces.

  • Anneals steel completely - Compared to other processes, lab furnaces can heat and cool materials like steel down to their core.

  • Works better for irregularly shaped objects - Objects in odd or irregular shapes tend to heat unevenly. A lab furnace makes heating objects more manageable and uniform, regardless of their thickness. 

  • Provides better temperature control Lab furnaces offer more accurate temperature control settings than other heat treatment equipment. As such, you have more control over the cooling and heating stages. This factor is essential when you're working with temperature-sensitive materials and alloys.

  • Offers automated options – You can reduce the manual labor needed for the annealing process by automating it through a lab furnace. All you need to do is set the heating and cooling rates, then insert the material inside.

Heat the Competition with High-Quality Furnaces


Heat treatment methods can be cumbersome when you don't have the correct type of equipment. As such, you must invest in quality lab equipment to help you work more efficiently. 

Across International is an industry leader in manufacturing heat treatment, laboratory, and material processing equipment. We carry a wide range of CE- and ETL-certified laboratory furnaces, including muffle, tube, and rotary furnaces, that are powered by Mitsubishi high-grade alumina ceramic and fiber and high-performance Kanthal heating elements.

Our heat treatment furnaces are designed to improve your day-to-day operations and overall lab productivity. All our lab furnace products also come with built-in temperature and safety cut-offs to prevent combustions and other accidents.

Choose from our quartz and ceramic tube lab furnace options of up to 250 MM OD. You can check them out in our online store, or get a quote from our team today.