Low hydrogen annealing

Low hydrogen annealing is a heat treatment in metallurgy

Metallurgy

Metallurgy is a domain of materials science that studies the physical and chemical behavior of metallic elements, their intermetallic compounds, and their mixtures, which are called alloys. It is also the technology of metals: the way in which science is applied to their practical use...

 for the reduction or elimination of hydrogen in a material to prevent hydrogen embrittlement

Hydrogen embrittlement

Hydrogen embrittlement is the process by which various metals, most importantly high-strength steel, become brittle and fracture following exposure to hydrogen...

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Process description

The material is kept in an hydrogen annealing oven over several hours at temperatures between 200 °C and 300 °C. The enclosed hydrogen atom

Hydrogen atom

A hydrogen atom is an atom of the chemical element hydrogen. The electrically neutral atom contains a single positively-charged proton and a single negatively-charged electron bound to the nucleus by the Coulomb force...

s, known for hydrogen embrittlement are removed by effusion

Effusion

In physics, effusion is the process in which individual molecules flow through a hole without collisions between molecules. This occurs if the diameter of the hole is considerably smaller than the mean free path of the molecules...

. The method is predominantly used immediately after welding or galvanizing of the parts.