ISO 14001 Certificated
Family Run Firm
Local Community Support
Which is better, hard anodised aluminium or stainless steel?
For modestly stressed parts, hard anodised aluminium is a low-weight alternative. The density of aluminium alloys are roughly one-third those of stainless steel alloys. The coating is hard and corrosion resisting.
Hard Anodising Ltd provides this treatment on a variety of aluminium parts.
What is anodising in plain English?
When bare aluminium is exposed to oxygen in the air, it reacts to form aluminium oxide at its surface. After a short time, this layer of oxide is too thick for the oxygen to penetrate and react any further as the oxygen has not sufficient energy at normal temperatures and pressure. This oxide layer is relatively chemically stable. Anodising develops on this natural process to make a thicker, denser and harder film on the metal by using electrical force to increase the speed and energy of oxygen molecules hitting the aluminium surface.
Hard Anodising Ltd provide a range of anodising process, including Hard Anodising, Sulphuric acid anodising and chromic acid anodising.
What are the disadvantages of electroless nickel plating?
Compared to hard anodising, electroless nickel is more expensive per unit volume of coating. ENP materials and their disposal involve more processing.
Like many heavy metals, nickel is an allergen, so ENP has little application in surgical equipment and industries such as food processing.
Hard Anodising Ltd offers a range of surface treatments including Electroless Nickel Plating.
What does Alocrom do?
Alocrom is a Chromate conversion coating that can be applied to aluminium parts by dipping, spraying, or painting. Alocrom provides corrosion resistance. Alocrom improves paint adhesion and is electrically conductive. Hard Anodising Ltd offers this treatment to AMS 03-18 and MIL DTL 5541.
What is the difference between anodising and hard anodising?
Hard anodic films form when the electrolyte is near freezing. Additionally, the charge carrier concentration is lower in hard anodising, whilst voltage is high. HA coatings have superior abrasion resistance to SAA coatings.
Hard Anodising causes loss of fatigue strength in highly stressed parts by up to 50%. By sealing in a sodium dichromate solution, one can restore fatigue strength. HA coatings have more fatigue strength loss than SAA coatings.