Annealing is a type of heat treatment of metals carried out to improve certain properties such as hardness and to remove the effects of certain operations (hardening, forming). It is carried out by heating to an "annealing temperature" and then cooling. We carry out the following types of annealing:
This is carried out when we need to achieve the lowest possible hardness, usually for machining purposes.
Annealing to reduce internal stresses
This is carried out when we need to remove internal stresses from a component caused by previous machining, e.g. by large material removal during milling. The parts show less deformation after future hardening.
Used to remove unevenness in the structure caused by previous machining (forgings, castings). It refines the austenite grains and thus improves the mechanical properties, therefore it is used for all steels 12-16.
Consists of heating (cold-formed steels) to a temperature where the hardening induced by previous cold forming is removed. It is used as an intermediate annealing during cold forming, especially for parts with low carbon content (up to 0,5%).
It is performed on stainless austenitic steels and some other steels that are hardenable. After heating to an annealing temperature that ensures the formation of a homogeneous solid solution, it is followed by rapid cooling.
We also carry out annealing of Cu alloys and stabilising annealing.
Refining of Al alloys
The refining of Al alloys is carried out by heating the alloy to an austenitising temperature of about 510°C and then cooling it rapidly with compressed nitrogen. This is followed by heating to the hardening temperature. The parts are minimally deformed and still meet the condition for Al alloy hardening.
Capillary brazing (Ni, Cu, solder)
Capillary brazing is a type of heat treatment that produces a solid (non-breakable) connection of two or more pieces of steel parts into a single unit. It is performed with Ni or Cu soldering irons.