Steel is a commonly-used material available in a variety of forms and grades. Mild steel is one of the most common forms and has a lower carbon content. This steel is also comparatively soft. Some other forms of steel have a far higher carbon content, making the steel both extremely tough and very resistant to shaping or cutting.
If you want to know how to soften hardened steel, then read on.
What is the softening of steel?
One of the main reasons for softening steel is to make the material malleable for shaping and cutting; then the steel is hardened again into its final form. This process is used to transform steel components. Softening steel is usually done by lasers. These are ideal tools for this process because they are flexible and able to work in high-precision environments.
How do you soften hardened steel?
Heat treatment that uses diode lasers is the best way to soften hardened steel. The solidified structure is softened in particular zones through heat exposure (also referred to as tempering), followed by slow cooling. The end result is steel that is shapeable and used for welding, forming or cutting.
Lasers are a good choice for this process because they are highly flexible and precise. They also create smaller transition zones between processed and unprocessed raw materials compared to other forms of technology. Lastly, diode lasers involve a homogenous intensity distribution even in larger spots, which leads to even softening across the material. Gas and infrared radiators don’t offer the same process quality for softening steel.
Here is the process for softening steel:
- Put the steel in a forge or a heat treat oven.
- Slowly raise the temperature of the steel meeting in a particular austenite region. Note that this temperature region is different depending on the grade of steel. You can usually find this temperature via the foundry that produced the material.
- Keep the steel at the designated austenite temperature for thirty minutes. The longer you keep it at this temperature, the higher the chance that the whole piece of steel will be annealed.
- Slowly lower the temperature of the steel—how slow depends on the steel’s grade. The temperature drop can be as slow as 5°F per hour.
- The steel should be cooled to room temperature.
- If you’re machining annealed steel, then make sure to not let the machine heat the steel too much. If it does, it may begin to heat treat, leading to hardening the steel.
- Note that annealing steel is a process that involves intense heat. Be sure to use the right safety equipment and procedures. Failure to do so could result in serious burns and other injuries.
We hope this answers some of your biggest questions about the softening of steel. Here at J.F. Heat Treating Inc, we offer professional metallurgy and heat treatment services. Our team of professionals provides all types of heat treating services to soften, harden, relieve stress or remove contaminants from your metal parts and components. Contact us right now to find out more.