April 8th, 2019
Achieving the perfect metal properties often requires heat. There are many different ways that heat can alter the properties of metal. Some of those methods include case hardening, tempering steel, precipitation hardening, and vacuum heat treatment. However, does heating metal make it weaker? Here are some common ways that heat treating metals changes the basic properties and strength of metal.
Metal Transformations
Metals can be changed to acquire or improve certain traitsthat are important for different roles in different industries. If needstructural elements for architecture, you’ll search for a material with verydifferent qualities than electrical wiring. Here are three basic ways thatmetal is transformed with heat treatment:
- Structure:By displacing atoms, heat can form new metallic structure. Also known asallotropic phase transformation, this is an essential transformation that isused with iron and steel heat treatment.
- Magnetism:Perhaps the most common way that heat makes metal permanently weaker is with amagnetic charge. Heating nickel, iron and cobalt to temperatures ranging from626 to 2,012 degrees Fahrenheit can cause these metals to completely lose theirmagnetism. Magnetism can be useful in some instances, but in others it can beunnecessary or inconvenient.
- ThermalExpansion: This transformation is not only used when crafting metalproducts but also can be a liability. Metal expands in volume, length andsurface area as it heats up. This can continue to occur even as the metal isshaped and put to use, so everything from sewer pipes to bridge cables needs toaccount for thermal expansion.
These are the basic ways that heat can alter thecharacteristics of metal. However, when heated and cooled in specific ways atspecific temperatures, heat can alter metal in far more unique and specializedways. Learn how heat treatment can specifically alter metal to fit a variety ofdifferent needs such as malleability, hardness, softness, magnetism and more.
Heat to Alter Metal
The short answer to the question regarding making metal weakis yes, however, only for some metals. The process of annealing can soften a varietyof metals. Brass, steel, iron copper and silver can all be made weaker byheating the metal to a set temperature and cooling it slowly. It’s not onlyused to create softer metal products but also more electrically conductiveones.
However, it would be incorrect to state that heat alwaysmakes metal weaker. Hardening is another process used by heat treatingcompanies to actually create more durable metal components. This is used forsteel and similar alloys and creates hard, yet brittle metal.
Another popular process where heat is used to alter metal istempering. Tempering increased the ductility of hardened steel. It is used tokeep the benefits of hard steel, with less of the brittle qualities.
Finally, normalizing alloys is another common way to treatmetal using heat. It starts with heated metal that is air cooled. This simpleact, if heated to an exact temperature range, can create a more pure, hardmetal. It’s often used to create steel that is stronger than annealing themetal, but also creates a less ductile product.
So, heat can indeed make metal weaker. However, there aremany processes where metal is strengthened by heat. The alloy, temperaturerange and cooling methods all need to be considered before determined whethermetal will increase or decrease its hardness through heat treatment.
Discover the Best Heat Treatment Service Whether you’re searching for weaker, more malleable metal through heat treatment or stronger, more durable products, SST offers one of the most professional and exacting steel heat treatment services in the country. Discover why we’re the only approved company for heat treatment of specific flight safety configurations.
If you have any more questions about heat treatment and metal processing, or if you need any services from one of the best heat treating companies in Michigan, contact us today.
