Through Hardening (also known as Quench & Temper) is a process used to produce high strength and good toughness when the entire part needs to be hardened (hence the name “through hardening”).

In through hardening, the metal is heated to form austenite, then quenched to transform the austenite to martensite, which has a much harder microstructure. Because martensite is brittle as well as strong, the part is then tempered (heated to a moderate temperature) to reduce the internal stresses caused by martensite formation during the quench.

Through hardening is ideal for moderate-to-high carbon steels, alloy steels, stainless steels, and tool steels. Steels with a carbon content below 0.2% cannot be hardened using a conventional quench and temper process.

Successful quench-and-temper operations depend on a thorough understanding of how the metal’s composition and treatment history will affect the result. Thermex’s experienced metallurgical engineers are fully expert in designing quench-and-temper operations for all grades of ferritic material. They’ll design a though hardening process to meet your specifications, or work with you to develop the process most suitable to your application.

All shop operations are carried out under an ISO 9001:2000 Registered Quality Management System.
Process quality controls include:

• furnaces are controlled by digital process controllers to ensure accurate process temperatures and reproducible results
• routine periodic quench analysis
• vertical quenching of long parts to minimize distortion
• nitrogen quench atmosphere available for scale-free tempering
• random microstructural analysis of test coupons run with through hardening loads
• temperature uniformity surveys of furnaces