Corrosion Testing

Corrosion. can be defined as a chemical or electrochemical reaction between a material, usually a metal or an alloy, and its environment that generally leads to its deterioration. The word ‘Corrode’ . has been derived from the Latin ‘Corrodere’. , which implies “to gnaw to pieces”. It is, more often than not, a degradation process which results in the loss of function of the affected material, and the degree of severity of corrosion depends on a number of factors, but primarily on the environmental parameters like humidity, temperature, chemical composition of corrodants, etc. Aqueous Corrosion, or Corrosion in environments containing water, is the most common or prevalent form of corrosion and water is arguably the most potent agent for this erosive process. The most common and well-known example of corrosion is ‘Rusting’. of iron.

Types of Corrosion

Corrosion can be classified into a number of different types. depending on the physical pattern or morphology of the attack. Some of the types of aqueous corrosion are: Uniform or general corrosion, Pitting corrosion, Crevice corrosion, Galvanic corrosion, Erosion corrosion, Inter-granular corrosion, and environmentally assisted cracking.

Effects of Corrosion

Corrosion affects a number of different materials, made of metals and alloys, and the effect can be seen in domestic buildings and industries. The need to be aware and conscious of corrosion stems from the fact that corrosion causes huge economic losses, endangers human safety, and can also adversely affects our environment. Examples of prodigious economic loss due to corrosion include electrical power plants and chemical processing plants. Shutdown of such plants can occur due to corrosion.

Importance of Corrosion Testing

Prevention of corrosion can be effected by various means, and thereafter the importance of ‘Corrosion testing’ can be appreciated. ‘Corrosion testing’ or ‘Corrosion Resistance Test’ is aimed at checking the ability of the test material to withstand the artificially induced corrosive environment, without disintegration. Various tests of corrosion exist, and they relate to the different types of corrosive environment that the test materials can be exposed to. The results from ‘Corrosion testing’ can also be used for ‘Failure Analysis’ of a number of commercially important engineering materials.

Modi Laboratory Laboratary is extremely competent to undertake any kind of Corrosion testing, and the testing activities are carried out exactly as per set standard conditions.

Intergranular Corrosion Tests

⋄ Oxalic Acid Test, ASTM A 262, Practice A

⋄ Ferric Sulfate - Sulfuric Acid, ASTM A262 - Practice B

⋄ Nitric Acid, ASTM A262, Practice C, (Huey Test)

⋄ Copper - Copper Sulfate - 16% sulfuric acid, ASTM A262 - Practice E (Straus Test)

⋄ Copper - Copper Sulfate - 50% sulfuric acid, ASTM A262 - Practice F

⋄ Salt Spray (Neutral / Fog), ASTM B117

⋄ Pitting Corrosion Test, ASTM Gr 48

⋄ Crevice Corrosion

⋄ Hydrogen-Induced Cracking (HIC) Test, NACE TMO284

⋄ Sulfide Stress Corrosion Cracking (SSCC), NACE TM 0177

⋄ Cyclic Corrosion test (CCT) started as per International Standards

Major Equipments

Chloride Stress Corrosion Test as per ASTM Gr 36 Specificatio