Metal corrosion refers to the destruction of metal under the action of chemical or electrochemical factors in the surrounding medium, and often under the combined action of physical, mechanical or biological factors, that is, the destruction of metal under the action of its environment.

The common types of metal corrosion in plate heat exchangers are as follows:

Uniform corrosion occurs on the whole surface of the medium or on a large area. The macroscopic uniform corrosion damage is called uniform corrosion.

Crevice corrosion will produce severe crevice corrosion in the crevice and covered part of metal surface.

Contact corrosion Two kinds of metals or alloys with different potentials contact each other and immerse in electrolyte solution. Current passes through them. The corrosion rate of metals with positive potentials decreases, while the corrosion rate of metals with negative potentials increases.

Erosion Corrosion Erosion corrosion is a kind of corrosion that accelerates the corrosion process due to the relative movement between the medium and the metal surface.

Selective corrosion of an element in a selective alloy is called selective corrosion because of its corrosion and preferential entry into the medium.

Pore corrosion concentrates on a few small points on the metal surface. The deep corrosion is called pitting corrosion, or pitting corrosion.

Intergranular corrosion is a kind of corrosion that preferentially corrodes the grain boundaries and the vicinity of the grain boundaries of metals or alloys, while the grain itself corrodes less.

Hydrogen destroys metals in electrolyte solutions, which can be destroyed by hydrogen permeation due to corrosion, pickling, cathodic protection or electroplating.

Stress corrosion cracking (SCC) and corrosion fatigue are the material fracture caused by the combined action of corrosion and tensile stress in a certain Metal-Medium system.