4 daily use products that undergo heat treatment and you didn’t know it

Historical drama movies and fantasy sitcoms have created a popular image of heat treatment, showing blacksmiths shaping metal alloys during the process of making weapons. Raising the temperature, followed by cooling the object in water, had been a common process for many centuries and served to make the iron in swords harder.

Nowadays, this type of procedure, which already has a modernized and automated version, is part of numerous manufacturing processes or materials processing. The heating process can confer properties such as: abrasion resistance, machinability, hardness, reduce tensions that can cause breaks, increase malleability for different materials.

Get to know some of the products and equipment of everyday use that receive heat for a certain time and temperature to guarantee the necessary properties for their efficiency:


Seat belt

Seat belts are a mandatory item in cars, trucks, and airplanes. When used in accordance with traffic laws, seat belts reduce the harm caused to drivers and passengers in the event of an accident. Here’s an interesting fact: The three-point belt, the most common model used in cars, reduces fatigue for drivers forced to drive for long periods (compared to drivers who do not use the equipment). By wearing the belt, the driver is forced to maintain an upright posture.

According to the Brazilian Traffic Safety Institute, during an impact, a vehicle traveling at 50 km/h can throw a 70 kg person with the force of 2450 kg. The metal parts that hold the belt to the seat go through a heat treatment to obtain the necessary hardness and strength for impact situations. This serves to protect the people inside the vehicle.


Crystals and semi-precious stones

Before they become commercially interesting, amethysts, rubies, and sapphires are just some of the stones that receive heat treatment. By applying heat, the stones change in intensity from their original color or change to other shades.

The process of heating them to a specific temperature and then cooling them is also able to turn turbid, low commercial value stones into more crystalline ones.


Contact and eyeglass lenses

Produced from a polymer composition, contact lenses and corrective lenses for glasses need to be heat-treated to be molded. The parts need to reach glass temperature, which makes them malleable enough to be shaped into the desired curvature.


Pressure cooker

In addition to the metal of the pan and the plastic components of the handle and vent pipe, the sealing ring that ensures the necessary pressure to raise the water temperature above 100 °C (212 °F) is made of a silicone rubber (elastomer). In the manufacturing process, sealing rings with this composition go through a vulcanization heat treatment, which makes them acquire different properties according to the process itself and the size of the silicon and oxygen atom chain.


Heat treatment is part of the creation process of countless items of daily use. From plastics, glass, ceramics to metals, all of them pass through industrial ovens and molds before leaving the factory plant and heading to the stocks of physical and virtual stores.

The quality assurance and reliability of these materials depend on adequate treatment, carried out in efficient furnaces and with the required temperature control. Controlling and measuring with precision, one of NOVUS specialties, is the best way to guarantee the quality of the product.