- story by MaterialDistrict
MAGOXID-COAT® is a plasma chemical coating that improves magnesium alloys.
The MAGOXID-COAT® layer is a crystalline oxide ceramic with a high content of extremely resistant compounds such as spinels, e.g. MgAl204. The plasma-chemical process produces oxide ceramic layers, which, in addition to providing a high level of protection against wear and corrosion, also meets other requirements such as hardness, uniform layer formation, fatigue strength, dimensional accuracy and temperature load capacity.
The MAGOXID-COAT® plasma chemical process is suitable for the coating of almost any magnesium alloy as well as for the treatment of alloys containing noble earths and zirconium. With a density of just 1.74 g/cm3, magnesium is the lightest of the metals used for construction. MAGOXID-COAT® can improve the surface properties of almost any magnesium alloy. This coating makes it possible to use coated magnesium products in different sectors, for example: rollers, clutch components, sealing units or conveyor guide rails. Possible industries include:
Valves and fittings
Office and data technology
Coating takes place in a saline electrolyte solution. The component is connected in series to an external source of electricity and acts as an anode. During anodization oxygen plasma discharges itself on the component surface and briefly melts the surface thus forming 2 oxide ceramic layers that bond tightly with the outer metallic layer. A barrier layer with a thickness of about 100 nm constitutes the direct bond with the magnesium component. Following the barrier layer comes an oxide ceramic layer with low porosity density followed by one with high porosity density. This layer bond protects the magnesium against wear and corrosion and, thanks to its surface structure, it allows the absorption of lubricants as well as following treatments such as paintwork or impregnation.
One variant of the MAGOXID-COAT® process is MAGOXID-COAT® black. This layer contains fade-resistant, chemically inert spinels of magnesium-aluminum oxide minerals and it is well suited for the treatment of virtually any magnesium-based material. For instance, MAGOXID-COAT® black is used for the inner coating of optical components or precision screw threads. It is ideal for heating radiators, for use in vacuum technology, microelectronics and in the aerospace industry.