Atmospheric corrosion of magnesium (Mg) alloys

Review of the atmospheric corrosion of magnesium alloys

“…Mg alloys show good resistance in dry air and little or no corrosion occurs. Atmospheric corrosion depends on the availability of water, and generally proceeds by means of electrochemical reactions under an aqueous layer or in droplets on the Mg surface [13,45]. The electrolyte allows ionic electrical paths and permits galvanic corrosion cells.…”

“…Relative humidity (RH) plays the most important role among all the environmental factors. Mg can be very corrosion resistant in dry air at ambient temperature [13,45]. However, when RH increases and reaches a certain level, the corrosion of Mg will change from a relatively slow chemical process to a significantly fast electrochemical reaction.…”

“…Chloride is one of the most corrosive species, which can induce breakdown of the Mg surface oxide film, resulting in rapid Mg corrosion [13,66,101,112,113].…”

“…primary α-Mg and eutectic Mg phase). In a marine environment, the air borne particles are mainly soluble particles, such as sea salt [13] containing chlorides that accelerate Mg corrosion.…”

“…They are considered for a wide range of uses in the aerospace and automotive industries, and for biodegradable implants [3][4][5][6][7][8][9][10][11][12]. However, their range of applications is more restricted than that of aluminum alloys due to their poorer corrosion behavior [13][14][15][16]. Common corrosion protection methods for Mg alloys include microstructure control [17,18], composition modification [19][20][21], and surface treatments and coatings [22][23][24][25][26][27].…”