Continuous Heat Treatment

The Continuous Heat Treatment Process at Emerson Forge Pvt. Ltd.

Heat Treatment Process

Attaining desirable mechanical properties is the key step of forging manufacturing. Mechanical properties are the ones that decide the quality and durability of the forgings. To come up with highly durable and desirable forgings, the engineers at Emerson go for specific heat treatment processes. They work at the microstructure levels to get the best outcomes. We follow the three-step heat treatment process (as per the standard procedure), which is as follows:

1. Heating beyond the critical temperature
Our experts calculate the metal or alloy’s critical temperature value and heat the metal beyond that temperature to attain changes in its microstructure and further its metallic characteristics.

2. Holding the metal at the heating temperature
Holding the metal at a specific temperature (heating temperature) ensures that the entire metal has a uniform microstructure. Heating furnaces are specifically designed to maintain this temperature.

3. Cooling
The metal is further subjected to lower temperatures for Microstructure Transformation. The final outcome is metal with desirable mechanical properties. At Emerson, we generally use a furnace with a well-regulated temperature to cool the metal. Sometimes, air cooling is also preferred by our engineers.

It often happens that a single heat treatment cycle cannot alter the microstructure of the entire metal. Hence, our engineers alter the duration of all the three steps to get the best results.

Types of heat treatment processes

At Emerson, we perform six different types of heat treatment processes. The factors considered for choosing one of them are as follows:

  • Types of material
  • The requirement of the forging
  • Steps performed before machining of the forgings.

Here are the details about all the treatment processes:

Controlled cooling

Forgings need to remain soft until they are placed in machines to avoid breakage. To avoid a heating cycle between the heat treatment and machining, our engineers have an excellent setup where the cooling process is controlled, and the forgings remain soft while machining. We design the process to eliminate all the brittleness existing in the forgings to ensure that they work efficiently in the long run. Apart from this, the process turns out to be environmentally friendly, which makes it more sustainable.


Our engineers never miss ensuring the microstructural homogeneity in the forgings. Hence, they choose to run a normalization cycle where they heat the metal around 30oC – 40oC above the critical temperature, hold it until it is homogenous, and gradually cool it down. We generally perform this process on forgings that demand higher toughness. They are subjected to multiple heat cycles, but a homogenous toughness is attained by normalization.

Iso annealing

We usually perform this technique on Alloy Steel to make them fit for machining. Initially, we heat the metal at higher than the critical temperature, hold it for some time, and then start cooling it isothermally. We complete the entire process in around 6 to 8 hours (Based on Shape & Size), i.e., faster than almost all the heat treatment procedures.

Hardening, Quenching, and Tempering

The metal hardening process at Emerson is always followed by tempering. The metal is heated above its critical temperature based on the CTT & TTT diagram of the steel grade. The metal is then immediately immersed into a quenching media. Both processes provide hardness and improved stress tolerance to the material. The metal still lacks toughness, due to which it retains brittleness to an extent. Hence, the metal is then exposed to low-temperatures for enhancing the hardness to toughness ratio. This process is termed tempering, which is always followed by hardening and/or quenching to ensure better strength of the material.

Continuous Heat Treatment facilities at Emerson forge Pvt. Ltd. are among the best setups with a blend of state-of-the-art machinery and technology.

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