Tufftride QPQ Treatment
Salt Bath Nitriding for Wear, Fatigue and Corrosion Resistance
Tufftride Q and QPQ are advanced salt bath nitriding processes carried out by Subcon Group within its UK manufacturing operations, designed to improve surface hardness, fatigue strength and corrosion resistance of steel components without compromising dimensional accuracy. The process introduces nitrogen into the surface of the steel at relatively low temperatures, forming a hard compound layer and diffusion zone that enhance surface performance while preserving core properties. Tufftride Q and QPQ are widely specified for components that require improved durability and long-term reliability under demanding operating conditions.
Low-Temperature Surface Enhancement Through Nitriding
Unlike hardening or carburising processes that rely on high-temperature phase transformation, Tufftride Q and QPQ operate at sub-critical temperatures. This allows nitrogen to diffuse into the steel surface without altering the core microstructure. The result is a hardened surface with excellent resistance to wear and fatigue, combined with minimal distortion. Subcon Group applies these processes where tight tolerances, surface integrity and predictable dimensional control are essential to component function.
The Q and QPQ Process Difference
Key Advantages of Tufftride ffride Q & QPQ with Subcon Group
- UK-based manufacturing with specialist salt bath nitriding capability
- Improved surface hardness and fatigue resistance without core embrittlement
- Minimal distortion due to low processing temperatures
- Enhanced corrosion resistance, particularly with QPQ treatment
- Smooth, uniform surface finish suitable for precision components
- Reduced friction and improved running-in behaviour
- Consistent and repeatable results across production volumes

UK-based manufacturing with specialist salt bath nitriding capability

Improved surface hardness and fatigue resistance without core embrittlement

Minimal distortion due to low processing temperatures

Enhanced corrosion resistance, particularly with QPQ treatment

Smooth, uniform surface finish suitable for precision components

Reduced friction and improved running-in behaviour
Frequently Asked Questions
Tufftride Q and QPQ form part of Subcon Group’s specialist surface engineering and heat treatment capability delivered within the UK. By combining salt bath nitriding expertise with disciplined process control, Subcon Group provides reliable, high-quality surface enhancement solutions that improve durability without compromising precision.