Heat Treatment Services UK

Heat treatment alters the physical and mechanical properties of metals through controlled heating and cooling cycles. It is one of the most critical processes in manufacturing, determining whether a component will have the hardness to resist wear, the toughness to absorb impact, the ductility to be formed, or the stress-free condition necessary for dimensional stability during machining. UK heat treatment companies provide these essential metallurgical services to manufacturers across every industrial sector.

This category lists UK heat treatment companies who offer thermal processing services on a subcontract basis.

Processes

Through-hardening and tempering produces uniform hardness throughout the cross-section of the component, commonly used for tool steels, spring steels, and medium-to-high carbon steels. Case hardening processes — including carburising, carbonitriding, and nitriding — produce a hard, wear-resistant surface layer while maintaining a tough, ductile core, ideal for gears, bearings, shafts, and other components subject to surface wear and bending or impact loads.

Induction hardening uses localised electromagnetic heating to harden specific areas of a component — such as bearing journals, gear teeth, or cam surfaces — without affecting the properties of the surrounding material. This process offers precise control over the depth and pattern of hardening and can be integrated into production lines for high-volume automotive and industrial applications.

Stress relieving removes residual stresses from welded fabrications, machined components, and castings, reducing the risk of distortion during subsequent machining or in service. Normalising refines grain structure and improves uniformity in forgings and castings. Annealing softens material for improved machinability or formability. Solution treatment and ageing (precipitation hardening) develop the full strength of aluminium alloys, nickel superalloys, and some stainless steels.

Atmosphere and Vacuum Processing

Controlled atmosphere furnaces (using endothermic gas, nitrogen, or argon atmospheres) prevent surface oxidation and decarburisation during processing. Vacuum heat treatment provides the cleanest possible processing environment, essential for aerospace components, precision tooling, and medical devices where surface contamination is unacceptable. UK vacuum heat treatment companies operate furnaces with temperature uniformity surveys to AMS 2750 or CQI-9 standards.

Search UK heat treatment companies in this directory by process type, material capability, furnace capacity, and sector accreditations including Nadcap, CQI-9, and aerospace prime approvals.