kaizenlab-quality

Heat Treatment

Kaizen Lab has the availability of 3 Nabertherm furnaces with the following capacity:

  • 250x250x180 mm
  • 500x500x600 mm
  • 750x750x1000 mm
Solubilization

The solubilization is a heat treatment applied on the austenitic steels (stainless steels and duplex) and it provides the heat at high temperatures, the nit follows a rapid water or inert gas cooling, in order to solubilize the chromium carbide precipitates (intergranular corrosion responsible).

Quenching

The quenching is a rapid cooling execute from high temperature, it inhibits the intrinsic diffusivity of the material that would recover the thermodynamic equilibrium. The vacancy quantity that is typical of the high temperature is preserved even at room temperature thanks to this process, providing a generally higher mechanical resistance.

Tempering / age hardening

The tempering or age hardening is applied in order to reduce the negative effects of the quenching process, as an example the excessive hardness that denotes fragility. The specimen is heated up to a temperature that is sufficient to recover the diffusivity of specific elements that could finely disperse in the metal matrix.

Quenching and tempering

The quenching and tempering is two step heat treatment: in the first step the quenching is applied, in the second step the tempering is applied.

Annealing

The annealing is a heat treatment with a heating temperature that is generally lower than the fusion temperature, with a permanence stage and a slow furnace cooling. The annealing permits to reduce the minor segregations, to transform the metastable phases and to reduce the residual stresses, hardening included.

PWHT (Post-Weld Heat Treatment)

The PWHT (Post-Weld heat Treatment) is applied after the welding process. The welds can locally alter the material, with imperfections and problematic localized interfaces between weld zone and base material. This treatment is useful in order to avoid the HIC (Hydrogen Induced Cracking) and to reduce the residual stresses.

Step Cooling

The step cooling is a thermic process subdivided into various steps and it is used to simulate the embrittlement that will be verified through a series of impact tests at various different low temperatures. From this test it is possible to extrapolate the transition curve.

References:

Duplex and stainless steel – https://en.wikipedia.org/wiki/Stainless_steel

Quenching – https://en.wikipedia.org/wiki/Quenching

Vacancy – https://en.wikipedia.org/wiki/Vacancy_defect

Tempering / age hardening – https://en.wikipedia.org/wiki/Tempering_(metallurgy)

Annealing – https://en.wikipedia.org/wiki/Annealing_(metallurgy)

Segregation – https://en.wikipedia.org/wiki/Segregation_(materials_science)

HIC (Hydrogen Induced Cracking) – https://en.wikipedia.org/wiki/Hydrogen_embrittlement