Tempering
After hardening, all steels exhibit reduced plastic properties and undesirable stresses.
To eliminate these issues, a heat treatment procedure is performed, which involves heating the previously hardened material, followed by holding at a specific temperature and controlled cooling to achieve the optimal structure and properties.
Tempering – Hart-Tech Service
We offer low, medium, and high tempering services within the temperature range of 180-650°C. It is possible to carry out the processes in the presence of a protective gas atmosphere, as well as, for highly customized requirements concerning the highest purity, the implementation of vacuum tempering.
Tempering involves heating previously hardened steel items to a specified temperature (depending on the desired effect, within the range of 180-650°C), holding them at that temperature, and then cooling them.
Depending on the temperature used, tempering is classified into low, medium, and high-temperature ranges:
Low-Temperature Tempering
is performed at temperatures ranging from 160°C to 250°C, with the goal of relieving hardening stresses while maintaining high hardness and wear resistance. It is primarily used for tools, springs, gauges, and carburized components.
Medium-Temperature Tempering
is performed in the range of 250-500°C and aims to achieve high strength and elasticity; however, hardness is significantly reduced. It is applied to springs, dies, leaf springs, parts of mechanisms such as pneumatic hammers, automotive components, and more
High-Temperature Tempering
is performed at temperatures above 500°C but below Ac1. The goal is to achieve the highest impact toughness possible for the given steel.
In some high-alloy steels, especially high-speed steels, tempering at temperatures between 500-600°C results in an increase in hardness (known as secondary hardness).
This phenomenon occurs due to the precipitation of highly dispersed carbides of alloying elements (such as W, Mo, V, Ti) that dissolved into the solid solution during austenitizing. These carbides form at temperatures that allow the diffusion of metal atoms, replacing the cementite that had formed earlier in the process.
Max. working chamber dimensions for tempering:
We offer tempering processes in atmosphere furnaces with a maximum load capacity of 1800 kg gross, in vacuum furnaces with a maximum load capacity of 1200 kg, and in pit furnaces. The sizes of the working chambers are as follows:
a = max 1200mm
b = max 900mm
c = max 750mm
Tempering, aging, and annealing in an atmosphere furnace:
a = max 1500mm
b = max 1000mm
c = max 900mm
Nitriding, sulfonitriding, tempering, aging, and annealing in a pit furnace:
h = max 1900mm
r = max 1000mm
