HARDFAST 1020 T consists in a special anodizing process that is obtained with impulse and frequency currents which are non-conventional or used in known processes obtained with pulse rectifiers with hardware and software that was studied for the described purposes after years of research and experimentation by ITALTECNO in collaboration with QUALITAL SERVIZI laboratories of Novara.

These current rectifiers are called “HARDFAST RECTIFIER”.

The HARDFAST anodizing technology uses a new generation additive (environmental-friendly and non-toxic) called HARDFAST ADD and it is essential to obtain the qualitative characteristics required by the anodic oxide produced with the HARDFAST process.

The process is completed by the mixing and cooling system of the anodizing bath. The system is composed of a refrigerator, heating exchange system and a special diffuser circuit type “ITALTECNO EDUCTORS” in order to obtain a constant temperature of the bath with an appropriate mixing of the solution for complete uniformity and quality of the anodic oxide.

OPERATIONAL PARAMETERS

PRETREATMENT: conventional with variations suggested according to the type of part to be treated.

ANODIZING:

• Concentration: H2SO4 170 – 200 g/l

HARDFAST ADD 20 – 30 g/l

(Liquid additive for anodizing)

• Temperature: 10 – 20 °C

(may vary according to the part to be treated and to the required hardness)

• Treatment time:

time depends on the required thickness and hardness (25-50% lower than conventional processes).

• Voltage and current density:

according to Italtecno know-how. Variable according to the parts to be treated and the required final characteristics. This special current waves are obtainable only using a special HARDFAST RECTIFIER.

SOLUTION MAKEUP

Add the Hardfast Add to the anodizing solution in order to reach the suggested concentration of 25 g/l.

CONSUMPTION

Working at the recommended conditions and including an average drag-out, the consumption should be 4 – 7 grams of HARDFAST Add for each square meter of aluminium processed.

MAINTENANCE AND CONTROL

Sulphuric acid can be determined with volumetric or potentiometric systems as in conventional baths.

Aluminium can be determined by volumetric method or by A.A. as in conventional bath.

ANALYSIS of HARDFAST ADD

Reagents required

Ceric Sulphate, 0.1N solution

• Oxalic Acid, 0.1N solution
• Ferrous Ammonium Sulphate (F.A.S.), 0.1N solution
• Ferroin solution, as indicator, prepared dissolving 1.485 g of ortho-phenanthroline monohydrate in 100 ml of ferrous sulphate solution (0.695 g of ferrous sulphate FeSO4 x 7H2O in 100 ml of water).

Procedure for the standardisation of Ceric Sulphate 0.1 N solution

• Pipette 25 ml of 0.1N Oxalic Acid 0.1 N solution in to a 400 ml beaker with 100 ml of distilled water.
• Add about 1 ml of Ferroin indicator and titrate with 0.1N Ceric Sulphate solution until the red colour disappears and the solution turns to persistant blue.

Calculations

Factor (F1) = ml of Ceric Sulphate 0.1N / 25

Note: Ceric Sulphate solution should be discarded when F1 < 0.80

Procedure for the standardisation of F.A.S.

• Pipette 25 ml of 0.1N Ferrous Ammonium Sulphate solution in to a 400 ml beaker with 100 ml of distilled water.
• Add about 1 ml of Ferroin indicator and titrate with 0:1N Ceric Sulphate solution until the red colour disappears.

Calculations

Factor (F2) = ml of Ceric Sulphate × F1 / 25

Note: FAS solution should be discarded when F2 < 0.80

BATH ANALYSIS

• Pipette 5 ml of anodising solution into a 400 ml beaker with 100 ml of water.
• Add with care 25 ml of 50% sulphuric acid solution and, using a pipette, accurately add 50 ml of 0.1N Ceric sulphate solution.
• Gently boil for 10-15 min.
• Cool and add distilled water to about 200 ml.
• Add about 1 ml of Ferroin indicator and titrate to a red end point with 0.1N Ferrous Ammonium Sulphate (FAS) solution. record the mls. of FAS as “A”

Calculations:

(50 × F1 – A × F2 ) × 1.3 = g/l of HARDFAST Add

Note: it is suggested to determine the factors for the standardization of the analytical solutions every time is necessary to make the analysis of the additive.

STORAGE

HARDFAST Add drums must be kept tightly closed during storage. It is good practice to keep all chemicals in a locked weather proof area to control access of unauthorized persons and to protect chemicals from the elements.

PACKAGING

HARDFAST Add is available in non returnable 25 Kg plastic drums.

For further information on HARDFAST or any other of the wide range of products Italtecno has developed for use in the aluminium finishing industry, please contact the Marketing or Technical Dept. of ITALTECNO S.R.L.