QUALANOD aluminum anodizing: part 2

See. part 1 - Flushing, travlenye, anodizing

filling the anodizing coating technology, which are based on methods, other than "hydrothermal filling"Or" cold soaking ", It can not be used without special tests and approval QUALANOD organization.

Cold filling is called "cold", because it occurs at significantly lower temperatures, than hot filling. Unlike hot fill, based on the hydration process, cold filling "working" on a chemical reaction between aluminum oxide and nickel fluoride. For this reason, “clean” cold filling without additional hot working is often referred to as non-sealing., impregnation.

5. hydrothermal filling

filling duration. filling duration, necessary for good filling, shall be not less than 2 minutes of 1 Coating thickness microns.

Filling in hot water. The water temperature in the bathtub filling should be below 96 ° C within, than 10 min after immersion therein cages.

phosphate, фториды и силикаты замедляют (ингибируют) процесс наполнения.

filling the steam. Minimum processing temperature must be the temperature of saturated steam.

6. Cold impregnation / cold filling

6.1. Первая стадия обработки: пропитка

Содержание ионов никеля: от 1,2 to 2,0 g / l
Свободные ионы фтора: от 0,5 to 0,8 g / l

The concentration of contaminants filling a bath, that can slow the process of cold filling, должна быть не выше указанных ниже:
sodium or potassium ions - 300 ppm;
ammonium ions - 1500 ppm;
sulphate ions - 4000 ppm;
phosphate ions - 5 ppm;
aluminum ions - 250 ppm.
If the bath is contaminated filling several of these substances, the "bad" content can occur at lower concentrations.

Технологические параметры:
Температура ванны: от 25 to 30 oC.
Величина рН: 6 ± 0,5.
Длительность пропитки: от 0,8 to 1,2 min / micron anodic coating.
Промывка: после пропитки обязательна промывка в холодной воде.

6.2. The second stage обработки: старение в горячей воде

To complete the CI-CS-treated in the first stage of the product should be placed for some time in an environment with very high humidity. Для этого применяют два варианта обработки:
1) стандартная обработка в воде при температуре не ниже 96 oC, but during the time of the calculation of the 0,8 to 1,2 минуты на каждый микрометр анодного покрытия;
2) в растворе сульфата никеля при его концентрации от 5 to 10 g / l at a temperature not lower than 60 ° C for a time in a proportion of 0,8 to 1,2 minutes per micrometer of anodizing.

Thorough rinsing between cold impregnating and treating in the hot water entirely obligatory, так как фторидные ионы могут ингибировать (замедлять) процесс гидротермического наполнения.

Anodic coating after cold impregnation is more susceptible to cracking, than after hydrothermal conventional filling, special, if it is placed in warm dry atmosphere. Processing in hot water after cold impregnating coating significantly improves crack resistance of.

6.3. Filling Quality Control

If the process of "cold-impregnation / cold filling" as performed as described above, including treatment in hot water, the coating may be filled with the same testing methods, as usual hydrothermal filling.

Наиболее подходящими методами контроля являются:

  • "Drop method" in accordance with EN 12373-4 (ISO 2143) and
  • weight loss method in accordance with EN 12373-7 (ISO 3210).

On the test methods and criteria for their results, see. Test methods anodic oxide coatings.

A source: QUALANOD Specifications, Edition 01.07.2010.