While small in scale, metal additive manufacturing is growing rapidly and placing new demands on heat treatment processes. In fact, heat treatment is an important part of achieving uniformity and consistency in finished parts, which will be essential if additive manufacturing is to make the transition from small-scale to mass production.
“Today, additive manufacturing is a very manual process where parts are transported physically from station to station for each step of the process,” says Dilip Chandrasekaran, Business Development Manager, Kanthal. “What we’ll see in the future as the industry grows is more automated processes where 3D printers feed parts into post-treatment. It will need to be smooth and streamlined, and the heating will need to perform different processes.”
As the parts manufactured become smaller and more intricate, new types of furnaces will need to be developed and customized specifically for the additive manufacturing industry.
Smaller and more intricate parts will require new types of furnaces.“It will require furnaces that can remove binders, sinter products and provide cooling,” adds Chandrasekaran. “But AM technology is moving so fast it is hard to predict.”
Transitioning to electric heating
Beyond additive manufacturing, manufacturers in many heavy industries are increasingly looking at electrifying their heat treatment processes. Many companies are already replacing gas heaters with electric, which not only eliminates emissions but also provides better control and predictability.
“The drive to improve sustainability, circularity, automation and digitalization – these are all affecting other industries so they will affect heat treatment as well,” says Chandrasekaran. “In heavy industries such as automotive, steel, aluminum and petrochemicals, which are large emitters of CO2, the drive to make a change is particularly strong.”
The pace of change is quickest in markets where electricity is cheap and readily available. This trend is clear in northern Europe but less so in the United States where natural gas prices are low, so the potential cost savings are not as obvious although still possible.
In many places, uncertainties around supply and demand of electricity will also hinder the transition. But overall, as stricter government legislation comes in, emitting CO2 will become more expensive through increased fees and taxes, and this will accelerate the drive toward electrification.
“The first step to making heat treatment carbon-free is to install electric heaters, and that is something that can already be done today,” says Chandrasekaran. “The next step is to use electricity from a fossil-free source. Then you’ve essentially eliminated all emissions from the process.”
The challenge for manufacturers of heating equipment will be to upscale their solutions. At present, electric heaters can replace gas heaters and gas burners in large installations such as in additive manufacturing. But to complete the transition in even larger industries, such as steel and petrochemical, even higher-power heaters will be needed.
Doing more with less
Flexibility is another growing demand when it comes to heat treatment technology, and over the coming decade equipment will be expected to perform multiple tasks within the same process.
“Rather than have separate steps and processes for quenching and annealing and so on, we will need to combine more functions in the same equipment,” Chandrasekaran explains. “This will reduce the production steps and therefore bring down the costs.”