OX-UHA is an innovative PEO (Plasma Electrolytic Oxidation) anodizing treatment for magnesium alloys which permits obtaining extraordinary characteristics of protection from corrosion and wear.
Main properties of PEO anodizing
Excellent wear resistance
Unlike traditional anodizing treatments, the
OX-UHA process uses high currents which create a plasma on the piece surface. The micro-melting is thus obtained of the oxide layer which mineralizes and compacts, thereby increasing hardness and wear resistance.
Excellent corrosion resistance
The compact layer of ceramic oxides protects the magnesium from corrosion in many aggressive environments, providing increased protection compared to traditional magnesium anodizing or chrome treatments.
Environment friendly, Cr6+
free
The process does not require the use of toxic chemical substances nor hexavalent chrome and therefore has a very low impact on the environment and human health.
Paintable
Thanks to the surface morphology, it ensures excellent adherence and can be subsequently painted. The combination of OX-UHA and painting permits obtaining very high corrosion resistance.
Technical specifications
Composition and applicable standards
| Composition |
| The OX-UHA treatment transforms the base magnesium into a compact layer of magnesium and aluminium oxides. |
| Mg |
O |
Al |
P |
Impurities |
| 35÷45% |
40÷50% |
5÷15% |
3÷7% |
Depending on the alloy |
| RoHS Conformity |
|
RoHS conform. No restricted-use substances beyond maximum tolerated concentrations. |
| REACh Conformity |
|
REACh conform. No SVHC in quantities greater than 0.1% by weight. |
Anodizable alloys
| Anodizable alloys |
| Magnesium alloys |
| All commonly used magnesium alloys |
Coating thickness and aesthetic appearance
| Coating thickness |
| Standard thickness |
Tolerance |
| 10µm |
±5µm |
| Thickness varies according to part geometries. Thickness is reduced in holes and internal areas. |
| Aesthetic appearance |
| Matt white colour. Surface roughness increases by about Ra 0.8-1.0. |
Tribological properties
| Hardness |
| The surface hardness of the OX-UHA varies according to the type of treated alloy. |
| Hardness value |
Alloy |
|
|
500±100HV |
AZ61 |
| Wear resistance |
| Thanks to the extra hardness of the layer, the OX-UHA treatment provides high wear resistance, superior to any other magnesium alloy treatment. |
Chemical properties
| Corrosion resistance |
| The compact layer of oxides of the OX-UHA treatment permits obtaining high corrosion resistance, superior to that provided by chrome coated magnesium alloys or by standard anodizing processes. |
| Approximate corrosion resistance value |
Alloy |
| NSS according to ISO 9227 - thickness 10 μm - corroded surface < 5% |
|
|
≥240 hours |
AZ61 |
| Chemical resistance |
| Approximate values of compatibility with the coating environment. The actual resistance to the environment must in any case be tested in the field. |
|
Hydrocarbons (e.g. petrol, diesel fuel, mineral oil, toluene) |
|
Alcohols, ketones (e.g. ethanol, methanol, acetone) |
|
Neutral saline solutions (e.g. sodium chloride, magnesium chloride, brine) |
|
Diluted reducing acids (e.g. citric acid, oxalic acid) |
|
Oxidizing acids (e.g. nitric acid) |
|
Concentrated acids (e.g. sulphuric acid, hydrochloric acid) |
|
Diluted bases (e.g. diluted sodium hydroxide) |
|
Oxidizing bases (e.g. sodium hypochlorite) |
|
Concentrated bases (e.g. concentrated sodium hydroxide) |
Production facility
