HEA (High Efficiency Anodizing)

Italtecno’s research laboratory has developed a new system for anodising which is able to improve:

 

  • efficiency (LOWER ENERGY COSTS)
  • consistency (BETTER REPRODUCIBILITY, less reject)
  • quality (HARDER AND BETTER CORROSION AND ABRASION RESISTANT ANODIC COATING)

of the anodic layer.

 

ADVANTAGES OF THE HEA PROCESS

Good quality of the anodic film and uniform colour tones achieved by a standardised, computer controlled process.

  • Quick or high speed anodizing (e.g. 20 micron produced in 20 minutes) without problems of aspect on natural colour (no greyish or yellowish film typical of other high speed processes) or of colorability (usually high current density anodising means green-greyish tones in electrocolouring and not consistency)
  • Recorded characteristics and quality of the anodic process: the computer records (and prints) all the parameters of the process ( like: voltage, current density, surface area, microns and temperature)
  • Multicolour and Greylox processes are improved by this special anodising process.
  • A computerised net work connection may be available between the customer’s machine and Italtecno laboratory.

 

THE RECTIFIER

The electrical current is supplied by a special machine able to give a pulsing current and is fitted with a special computer APC (Anodizing Process Computer) able to set and record:

 

– voltage

– current/current density

– temperature

– surface of each load

 

The machine reads the “electrochemical” area of the load and organises the proper current density (and voltage) of the anodic process in order to achieve the thickness of the anodic layer chosen by the customer.

 

The same current supplier is suitable for:

– architectural anodising

– hard anodising for any type of alloy

 

The anodic layer can be coloured with any standard two steps (electrocolouring) system in:

  • tin based solutions
  • nickel + tin solutions
  • cobalt solution

or with special colouring processes like Greylox, Multicolour or Interference colours.

 

 

THE COOLING SYSTEM

It is necessary to use a high efficiency system able to maintain the temperature at the fixed value (with a range of ± 1 °C) and to produce a correct circulation of the solution (Special suitable pump is supplied)

 

AIR AGITATION (MICRO-BUBBLE SYSTEM)

A correct air agitation, produced by special diffusers, is necessary to dissipate the heat generated on the anodic layer surface by Joule’s effect

A uniform stream of small-sized bubbles maintains the aluminium surface at the correct temperature.

 

THE ELECTROLYTE

The solution used for the anodising process is composed by:

– 180 g/l sulphuric acid

– 36 g/l HEA additive

 

 

OPERATIONAL CONDITIONS

Current density:                            in agreement with customer

Temperature:                      0 – 5 °C                  for hard anodising

19 – 20 °C               for architectural anodising

Speed of anodising:                     according to the operative   conditions (current density)

 

 

 

QUALITY OF THE ANODIC LAYER

The quality of the anodic layer is according to the European and International specification, including those concerning the characteristics of the anodic film (A.A.M.A. Specifications) and the “colorability” of the anodic layer is perfect even when produced at extreme conditions (e.g. high current density and temperature).