Frequently Asked Questions about Heat Treating Steel

We here at Hi-Tech Steel Treating often get asked the same questions about heat treating steel in Tennessee. So we’re going to covered some of the most frequently asked questions and give you more information about the heat treating steel process and how it can benefit you.

Can you hit a metal with another metal to determine hardness?

Depending on the type of metal, yes, you can. For example, a hard aluminum is more like a soft steel. You can try to use a scratch test, especially if you purchase a set of graduated files, which are specifically designed to test the steel’s (or other metal’s) hardness. 

What happens when the metal’s toughness is tempered down with hardness?

When the metal’s toughness is tempered, the toughness is not significantly affected by the tempering process. But you can improve the toughness through heat treating steel by using a lower hardening temperature and then cooling it completely to room temperature between the tempers. This will ensure a complete conversion.

Why are metals like steel, carbon and iron so hard?

The internal crystal structures are the cause. Non-ferrous metals can only be hardened through hammering, bending and rolling. But they are softened through the heat treating steel process called annealing. Steel’s hardness is determined by its carbon content. When you are heat treating steel, you have to heat it to a medium red color, or to just above the point where the steel becomes magnetic, and then dip it into water, air or oil.

Can you use a scratch test on glass, stainless steel or carbide?

You can, but it’s not as dependable. There are other, more reliable ways of testing these materials’ hardness.

When you need heat treating steel in Tennessee, call Hi-Tech Steel Treating, Inc. at 1-800-835-8294 or Contact Us.

Neutral Hardening: Definition and Importance

The process of producing a martensitic microstructure that is normally performed on ready-made parts is known as neutral hardening. Two other terms for this same procedure are “quench hardening” and “martensitic hardening.”

The reasons this process is performed, plus the reasons it’s so important, are numerous. First and foremost, the steel will achieve a higher level of strength and hardness, plus it will become tougher, more resistant to temperature extremes, plus the parts will be lighter and stiffer. Parts that require low-roughness grinding will get the needed machinability, and the martensitic stainless steel parts are corrosion resistant after neutral hardening. Tools are also more resistant to wear.

Neutral hardening will not change the chemical composition of the steel tools. It will help harden the tool’s core, but the surface will not change, so that means the heated parts of the surface are not enriched or decarburized. The steel tools will then have the best combination of strength and toughness and, if needed, the aforementioned temperature resistance. 

Steel tools will first be shaped. And then the actual neutral hardening process begins. It involves parts being heated in a neutral atmosphere. They are then quenched in an agitation- and temperature-controlled oil bath that is also furnace integral. This helps the parts to harden. Then the parts are tempered to relieve the stresses from the heat treating procedure. The part’s hardness is reduced to the desired hardness range during this part of the procedure. Parts that get this sort of heat treating process include springs, highly loaded parts, cutting and hammering tools and stainless steel tools that need high corrosion resistance.

Neutral hardening is a pretty complicated heat treating process, so it is imperative that you take your steel tools to a company that really knows what it is doing. That is where we come in! When you need neutral hardening services call Hi-Tech Steel Treating at 1-800-835-8294 or Contact Us.