Steel bar going through quench and temper process

The Quench & Temper Process

Although there are many processes that are involved in steel production, quench and temper is one of the most common ones used to modify a metal’s microstructure. Steel applications that require material that is harder, tougher, and less ductile are a few reasons why the quench and temper process is preferred. 

Keep reading to learn more about this process, and how it can streamline your steel production. 

What Is Quench & Tempered Steel?

All steel contains some carbon, which makes it harder. Too much carbon can weaken the steel’s integrity. The quench and temper processes are used to increase the mechanical properties of carbon steel without the addition of more carbon.

High-carbon steel has a 0.60 to 1.00% ratio of carbon content compared to the 0.05 to 0.25% ratio of mild steel. When high-carbon steel goes through the quench and temper process, its mechanical properties make it more wear-resistant and durable.

This process also exposes the metal stock to both rapid cooling (quenching) and re-heating with a slower cooling process (tempering). Both the quenching and tempering processes are responsible for adding strength and toughness to steel.

Steps in the Quench & Temper Process

Before quenching and tempering begin, material engineers must have already completed a time, temperature, transformation diagram (TTT). By adhering to specific time and temperature cycles, the metal’s grain can be predetermined.

The steps in the quench and tempering process include:

  1. Austenitizing cycle:  The steel is heated to an extremely high temperature which causes the metal’s grain to become austenite.
  2. Quenching: Next, the steel is rapidly cooled, which transforms the austenitic grain structure into martensite. The quenching process can be completed using either water, a polymer mixture, oil-quenched, molten salt (brine). 
  3. Tempering: This step improves the metal’s ductility and slightly reduces hardness. During this process, the metal heated to a specific temperature for a set period of time. Once the proper mechanical properties are achieved, the metal air cools.

Benefits of Quenched & Tempered Steel

As mentioned previously, there are many benefits of quenched and tempered steel, including:

  • Increased Strength
  • Increased Toughness
  • Less Distortion
  • Predictable Physical Properties


These benefits have contributed to the widespread use of quench and tempered steel for a host of infrastructure and construction projects, and have been essential to higher quality automotive, aerospace, and military components.

Here are some steel products that are made tougher and longer lasting due to the quench and temper process:

  • Machining & Cutting Tools
  • Bridge Erection
  • High-Rise Structures
  • Heavy Construction Equipment
  • Chemical Storage Tanks
  • Dump Truck Liners
  • Industrial Machinery
  • Stronger & Lighter Cars
  • Forestry Equipment

Turn to the Region’s Trusted Source for Steel Products

King Steel is one of the largest suppliers of quench and tempered steel bars. We have over 40 convenient locations across the U.S., and have been proudly serving clients for over five decades. When it comes to our steel products, we use the induction heat-treating process to ensure better wear resistance, strength, and longevity. 

If you’re interested in learning more about the quench and temper process, and how it contributes to better products, call us today. Browse our full line of steel bar and wire rod products. If you see something that you like, you fill out our form online to request a custom quote.