cold cracking

Information about cold cracking

Cold cracking is a defect that occurs in welding and requires all the following preconditions:
  • susceptible microstructure (e.g. martensite)
  • hydrogen present in the microstructure (hydrogen embrittlement)
  • service temperature environment (normal atmospheric pressure): -100 to +100 °F
  • high restraint
Eliminating any one of these will eliminate this condition.
Welding is a fabrication process that joins materials, usually metals or thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material (the weld puddle
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Martensite, named after the German metallurgist Adolf Martens (1850–1914), is any crystal structure that is formed by displacive transformation, as opposed to much slower diffusive transformations.
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1, −1
(amphoteric oxide)
Electronegativity 2.20 (Pauling scale) More

Atomic radius 25 pm
Atomic radius (calc.) 53 pm
Covalent radius 37 pm
Van der Waals radius 120 pm
Miscellaneous

Thermal conductivity (300 K) 180.
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Hydrogen embrittlement (or hydrogen grooving) is the process by which various metals, most importantly high-strength steel, become brittle and crack following exposure to hydrogen.
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