What is the main cause of intergranular corrosion in stainless steel?

Intergranular corrosion (IGC) is a selective attack in the vicinity of the grain boundaries of a stainless steel. It is as a result of chromium depletion, mainly due to the precipitation of chromium carbides in the grain boundaries.

How do you fix intergranular corrosion?

Fortunately, heat treatments can often resolve the issue and return the metal’s structure to a near-original state. In some cases, solution-annealing (also known as quench-annealing or solution-quenching) is an effective means of reversing intergranular corrosion damage in austenitic stainless steels.

How can we prevent intergranular corrosion?

Intergranular corrosion can be prevented through:

1. Use low carbon (e.g. 304L, 316L) grade of stainless steels.
2. Use stabilized grades alloyed with titanium (for example type 321) or niobium (for example type 347). Titanium and niobium are strong carbide- formers.
3. Use post-weld heat treatment.

When does intergranular corrosion occur?

Intergranular corrosion occurs when certain metals and alloys reach temperatures between 425°C and 870°C (887°F to 1598°F.) These temperatures are most common during welding, heat treatment, or operation in high-temperature environments.

What causes intergranular fracture?

Intergranular fracture occurs when a crack propagates along the grain boundaries of a material, usually when these grain boundaries are weakened. The more commonly seen transgranular fracture, occurs when the crack grows through the material grains.

Which of the following is are the causes of intergranular corrosion?

Explanation: Intergranular corrosion is the corrosion occurs between two or more grains. It causes due to the presence of a differential concentration of alloying elements at the grains and grain boundaries. Stainless steels are highly prone to this intergranular corrosion.

What is the primary cause of intergranular corrosion?

Intergranular corrosion is generally considered to be caused by the segregation of impurities at the grain boundaries or by enrichment or depletion of one of the alloying elements in the grain boundary areas.

What type of corrosion is intergranular corrosion?

Intergranular corrosion is a special form of microstructurally influenced corrosion, whereby the grain boundary ‘region’ of the alloy is electrochemically different to the bulk or adjacent alloy microstructure.

Where does intergranular corrosion occur?

grain boundaries
Intergranular corrosion (IGC) is a form of localized corrosion characterized by preferential corrosion at grain boundaries or areas adjacent to them, with little or negligible attack on the grains. Similarly to other forms of localized corrosion, it mainly occurs on passive alloys exposed to specific corrodents.

Which of the following are the causes of intergranular corrosion?

Which of the following is the causes of intergranular corrosion?

What conditions promote intergranular fracture?

Examples of solutes known to influence intergranular fracture are sulfur, phosphorus, arsenic, and antimony specifically in steels, lead in aluminum alloys, and hydrogen in numerous structural alloys.