*COOL PLUS* Sub-zero Cryogenic Treatment Vacuum Furnace

B5_R furnace equipped with *COOL PLUS* process

Key Advantages of COOL PLUS Sub-Zero Process

Eliminates residual austenite for improved metallurgical structure
Boosts hardness and fatigue strength (e.g., X20Cr13 steel reaches 690 HV after –100°C treatment, vs. 640 HV without)
Preserves the surface finish and brightness of treated parts
Reduces tempering cycle times and operational costs
Enhances competitiveness in tool, mold, and aerospace manufacturing.

Applications of Deep Freeze Heat Treatment

The *COOL PLUS* cryogenic furnace is particularly suited for:

High-speed steels
Stainless steels
Precision tooling
Aerospace and automotive components
Applications requiring extreme wear and dimensional control.

Sub-Zero Furnace for Deep Freezing Heat Treatment

The *COOL PLUS* process, patented by SCHMETZ and fully compatible with BMI's B5_R tempering furnace, is a sub-zero process designed for cryogenic treatment of steels. This deep freeze heat treatment is typically applied between quenching and tempering cycles to enhance the mechanical performance of components.

What is Cryogenic Heat Treatment?

Cryogenic heat treatment involves cooling parts to extremely low temperatures (between –40°C and –100°C) using liquid nitrogen injection. This process completes the martensitic transformation and reduces retained austenite, resulting in:

Increased hardness
Improved dimensional stability
Enhanced wear resistance
Superior brilliance of the component surface

How the COOL PLUS Cryogenic Furnace Works

Liquid nitrogen is injected and vaporized directly into the heating zone
A uniform sub-zero atmosphere is created using gaseous nitrogen
The cycle is fully automated and controlled for optimal repeatability and process stability
Ideal integration with tempering cycles for high-performance industrial heat treatment.