Intergranular corrosion

（重定向自Weld decay）

Intergranular corrosion (IGC), also known as intergranular attack (IGA), is a form of corrosion where the boundaries of crystallites of the material are more susceptible to corrosion than their insides. (Cf. transgranular corrosion.)

This situation can happen in otherwise corrosion-resistant alloys, when the grain boundaries are depleted, known as grain boundary depletion, of the corrosion-inhibiting elements such as chromium by some mechanism. In nickel alloys and austenitic stainless steels, where chromium is added for corrosion resistance, the mechanism involved is precipitation of chromium carbide at the grain boundaries, resulting in the formation of chromium-depleted zones adjacent to the grain boundaries (this process is called sensitization). Around 12% chromium is minimally required to ensure passivation, a mechanism by which an ultra thin invisible film, known as passive film, forms on the surface of stainless steels. This passive film protects the metal from corrosive environments. The self-healing property of the passive film make the steel stainless. Selective leaching often involves grain boundary depletion mechanisms.

单词	Weld decay
释义	Weld decay 英语百科 Intergranular corrosion （重定向自Weld decay） Intergranular corrosion (IGC), also known as intergranular attack (IGA), is a form of corrosion where the boundaries of crystallites of the material are more susceptible to corrosion than their insides. (Cf. transgranular corrosion.) This situation can happen in otherwise corrosion-resistant alloys, when the grain boundaries are depleted, known as grain boundary depletion, of the corrosion-inhibiting elements such as chromium by some mechanism. In nickel alloys and austenitic stainless steels, where chromium is added for corrosion resistance, the mechanism involved is precipitation of chromium carbide at the grain boundaries, resulting in the formation of chromium-depleted zones adjacent to the grain boundaries (this process is called sensitization). Around 12% chromium is minimally required to ensure passivation, a mechanism by which an ultra thin invisible film, known as passive film, forms on the surface of stainless steels. This passive film protects the metal from corrosive environments. The self-healing property of the passive film make the steel stainless. Selective leaching often involves grain boundary depletion mechanisms.
随便看	ostwald decade rheostat的意思 ostwaldde waelenetting power model的意思 ostwald de waele netting power model的意思 Ostwald diagram的意思 Ostwald dilution law的意思 ostwald equation的意思 Ostwald Folin pipet的意思 ostwaldfolin viscosimeter的意思 ostwald folin viscosimeter的意思 ostwald folin viscosimetre的意思 ostwaldfolin viscosimetre的意思 Ostwald Folin volumetric pipette的意思 Ostwald, FWilhelm的意思 ostwald glass capillary viscometer的意思 ostwald glass capillary viscometre的意思 Ostwald gravimeter的意思 Ostwald indicator theory的意思 Ostwaldite的意思 Ostwald law的意思 Ostwald pipet的意思 Ostwald pipette的意思 Ostwald process的意思 Ostwald ripening的意思 Ostwald rule的意思 Ostwald的意思