Through Hardening ("Quench & Temper") is a process used to increase the hardness and tensile strength of material, and in alloy steels such as 4140 and 4340, will result in optimum combinations of strength and toughness.
At Thermex, we have a variety of quench types available (oil, water, polymer, air blast), thus allowing for the through hardening of a wide range of materials including mild steels, alloy steels, tool steels, martensitic stainless steels, and cast irons.
Dimensional change is inherent in quench and temper heat treatments, because of the microstructural changes that occur.  For tight tolerance parts, finishing allowances are required.  Always avoid sharp corners and abrupt cross-section changes in parts that are to be through hardened.
Through Hardening
-Process Capacities-

Up to 92” long, 44” diameter,
3000 lb.
Vertical quenching up to 92" in pit furnace line
High capacity internal quench furnaces

Available Quench Types: oil, water, air blast

Process Selection and Quality Control

Success in through hardening depends on proper selection of process parameters (temperatures, atmosphere, quench type, cycle times), and in proper handling of the parts (fixture design) to reduce distortion and improve process uniformity.  Contact us to discuss your specific requirements before making final decisions about your part design - considering heat treating requirements ahead of time may eliminate problems during manufacturing. Sometimes, a simple change in material or heat treating process can make the part better suited to its intended purpose, at a lower overall cost.
All heat treating operations are carried out under an ISO 9001 Registered Quality Management System.

Process quality controls include:

  • Furnaces are controlled by digital process controllers to ensure accurate process temperatures and reproducible results, within a narrow band of temperature uniformity 
  • Routine quench analysis to ensure proper quench characteristics
  • Vertical quenching of long parts to minimize distortion
  • Nitrogen atmosphere available for clean tempering, when required
  • Random microstructural analysis of test coupons run with production loads
  • Temperature uniformity surveys of furnaces
  • When required, tensile and impact testing of customer supplied coupons to confirm mechanical properties

Contact Us for more information on our full range of metal heat treating services.