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Anodising aluminium profiles at Mifa

A process where strength and aesthetics come together to create a durable aluminium profile. What anodising exactly involves and what Mifa can do for you can be found on this page.

At Mifa, there are various possibilities and unique processes to enhance products, including the anodisation of aluminium extrusions. With our in-house surface treatment process, we go beyond just extruding aluminium profiles: by creating an additional protective oxide layer, we elevate products to an even higher level. Additionally, through an electrolytic treatment, we not only create an improved corrosion layer but also enhance aesthetics and achieve durability.

What is anodising?

Anodising is an electrochemical process in which aluminium is converted into aluminium oxide (Al2O3) in a controlled environment. By using electric current and an electrolyte (sulfuric acid) and continuously dissolving aluminium, a layer is formed with numerous pores.

An anodised layer is hard and brittle, with properties comparable to glass or ceramics. The layer may ‘break’ under strong bending, as it is an inherent material-specific layer with exceptional adhesion to the substrate, which is aluminium. Practical anodised layers range from 5 to 60 µm, depending on the alloy and application. The physical law governing the anodising process is Ohm’s Law: U = I x R, where Voltage (V) = Current (A) x Resistance (Ω).

Anodising is a galvanic process but with a reversed pole. The workpiece is connected to the anode, unlike standard galvanic processes (such as silver plating). During anodising, the resistance of the formed layer increases, influencing the anodising process/build-up speed, which is controlled by programmed process sequences.

Why anodise aluminum?

The anodisation of aluminium profiles provide advantages in terms of weight and (mechanical) workability. Some benefits of anodising that can contribute to the properties of aluminium include:

  • Corrosion resistance;
  • Wear resistance;
  • Optical requirements;
  • Insulation and reflection;
  • Adhesive base for paints or adhesives;
  • Sliding properties;
  • Non-stick.

What anodising options are available at Mifa Aluminium?

Mifa has fully automated production lines that are PLC-controlled, with continuous process monitoring. We can treat products up to a length of 3,600 mm, including all pre- and post-treatments. Our high-quality titanium (pre)stretch technology ensures high-quality standards and efficient production.

Mechanical pre-treatments Chemical pre-treatments Post-treatments
Blasting: machining in-house, glass bead via external partner Standard (dimensionally stable) pickling: products delivered at final dimensions retain their dimensions Colouring: absorbent color baths provide a deep black coloration; other colors are negotiable.
Tumbling: deburring and polishing technique using stones Matte pickling: a matting of the surface ensures retouching of irregularities (not dimensionally stable) Sealing: the open pore structure is compacted using hot water (96 °C), creating corrosion resistance
Belt grinding (Medium) gloss pickling: satin finish effect that also makes light scratches less visible (dimensionally stable is possible) Application of primers and/or paints through wet painting (for project-based applications)
Impregnation with polymers: see Tufram® in the polymer layers process group

Types of anodising at Mifa Aluminium

Mifa has three different anodising techniques: GLISSCOAT®, HART-COAT®, and technical anodising. Almost all alloys can be anodised, with the alloy being a determining factor for the color of the anodised part. Our engineers can provide advice on this.

GLISSCOAT® HART-COAT® (hard anodising) Technical anodising (normal anodising)
Specifications
  • Low friction factor
  • Counteracts slip-stick effect
  • Protection against corrosion
  • Can be tinted in black
  • Improves visual properties
  • Protects against wear and corrosion
  • Strengthens various components
  • Increases functional and decorative qualities
Applications
  • Mechanical engineering
  • Pneumatic sector
  • Automotive
  • Mechanical engineering
  • Automotive
  • Household appliances industry
  • Medical equipment
  • Pharmaceutical industry
  • Defense technology
  • Aerospace
  • Medical equipment
  • Electronics

Properties of anodised aluminium extrusions

During the anodising process, we achieve layer thicknesses ranging from 5 to 20 µm, depending on the profile’s application, desired layer properties, and other parameters for various markets. What makes Mifa’s anodising process unique is that we build only one-third of the oxide layer, while the remaining part penetrates the aluminium during anodising.

Key properties:

  • Maximum layer thickness: Up to 20 µm
  • Corrosion protection: Max. 2000 hours salt spray test – compliant with DIN 50021 ESS
  • Hardness: Approx. 250 HV 0.025, depending on the alloy
  • General standard: MIL-A-8625F Type I

Anodising aluminium profiles makes a sustainable contribution

Anodising aluminium profiles is a process that not only enhances the aesthetic value of aluminium but also makes a sustainable contribution to the industry and the environment. This process, which creates a protective oxide layer, has several sustainable benefits:

  • Corrosion resistance: anodisation forms a hard and durable oxide layer on the aluminium surface, making the profile resistant to rust and corrosion. This extends the lifespan of the aluminium components, resulting in less waste as they need replacement less frequently.
  • Energy efficiency: the anodisation process involves chemical reactions and electricity but occurs in a controlled environment. The energy consumption is relatively lower compared to alternative methods such as galvanization.
  • Recyclability: aluminium is naturally a recyclable element, and an anodised aluminium profile retains its properties during the recycling process.
  • Reduced harmfulness: anodisation serves as an alternative to traditional paint and coating systems, which often contain harmful solvents and chemicals. Anodisation contributes to cleaner production and reduced environmental impact.
More about sustainability

Unique bright-dip on the profiles of SodaTASTE

Together with our customers at Mifa, we create the best end product. With one of our knowledge partners, SodaTASTE, we have anodised aluminium bottles in colour. During the design phase, various steps were taken to achieve a unique product. A great example of how Mifa employs co-engineering to collaborate with the customer during the design phase.

More about this case study

Certifications

At Mifa, we hold various certifications, including IATF16949, ISO 9001, and ISO 14001. Additionally, Mifa, like Mifa, also holds the AS9100 certificate for the aerospace industry. This certification demonstrates that Mifa’s production and business facilities meet the high-quality standards required for the aerospace industry.

Get in touch with us

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Manager Surface Treatment