ISO 8080-2021 pdf free download – Aerospace — Anodic treatment of titanium and titanium alloys — Sulfuric acid process.
4.2Preparation for anodizing
4.2.1 Parts shall be thoroughly alkaline cleaned to ensure that all surfaces are free from contaminantssuch as grease, oil and mill markings.
4.2.2 Chlorinated solvents and methyl alcohol shall not be used for degreasing.
4.2.3 Parts shall be firmly attached to the racking device.Contact areas shall be kept as small aspossible and, when practicable, shall be on a surface not required to be coated. When parts are to becoated on all surfaces, contacts shall be located on areas indicated on the drawing.
4.2.4 Parts shall be oriented so as to minimize gas entrapment during processing.
4.2.5 After cleaning, parts shall be etched for a minimum duration to guarantee surface activation in anacid pickling solution (see 4.1.7) and then rinsed thoroughly in cold running water.Heavily scaled partswhich do not provide a clean, bright surface after the treatment outlined above may require fine aluminagritblasting or pretreatment in an oxidizing alkaline solution prior to etching.
NOTE Surface activation is correct when the surface is visually clean and bright.
4.2.6 As an alternative, a mechanical activation can be used for surface preparation if agreed betweenthe original equipment manufacturer (OEM) and the processor.
4.3Anodizing procedure
4.3.1 The parts shall then be immersed in the anodizing solution. The parts shall be made the anodeand the tank, or auxiliary plates, the cathode.Current shall be applied to reach the desired coloration.Recommended voltage cycle: from 15 V to 20 V for a period of 15 min or until the desired colorationhas been achieved.The recommended initial current density should be approximately 0,2 A/dm2, with areduction to an approximate value of 0,05 A/dm2 over the greater part of the anodizing cycle.
4.3.2 During processing of intricate parts, the solution should be agitated in order to minimizeentrapment of gas in pockets and blind holes. If necessary, parts should be repositioned periodically tobring the electrolyte into contact with uncoated areas and to prevent attack at the liquid/gas interface inpockets and blind holes.
4.3.3 After completion of the anodizing cycle, parts shall be rinsed thoroughly in cold, running water,then rinsed in clean, hot water and dried.
4.3.4 lf subsequent surface treatments are to be applied, parts should be handled and stored in such amanner as to avoid them being contaminated.
5Quality assurance provisions5.1 Responsibility for inspection
Unless otherwise negotiated, the processor is responsible for the performance of all quality assurancerequirements of this document.
5.2Visual examination
5.2.1 The coating shall be smooth and adherent, uniform in texture and appearance, and shall exhibit auniform blue-violet colour. It shall be continuous except at contact points.
5.2.2 Parts showing burned or powdery areas, loose film, discontinuities such as breaks or scratches,a yellow colour or any other damage or imperfection in the anodic film which may be detrimental to thefunction or performance of the parts shall be deemed to be unacceptable. Such parts may be repickledand reprocessed only after consultation with the quality assurance authority responsible.
5.2.3 Where required in the contract or order, the colour of the parts shall be substantially the same asthat of a similarly treated control sample of the same alloy in the same heat treatment state and with thesame surface finish as the parts being inspected.
5.3Approval
5.3.1 Sample coated parts and panels shall be approved by the purchaser and, if necessary, by thequality assurance authority responsible, before production parts are supplied, unless such approval bewaived.
5.3.2 Complete documentation of all quality control procedures and tests shall be made available tothe purchaser upon request.
5.3.3The processor shall use manufacturing procedures, processes and methods of inspection onproduction parts which are the same as those used on the approved sample parts. No deviation from theprocedures shall be permitted without re-approval by the purchaser.
6Packaging and delivery
6.1 Packaging
Anodized parts shall be packaged in such a manner as to ensure that the parts will be protected duringshipment and/or storage against damage due to mishandling, exposure to the weather, or any normalhazard.ISO 8080 pdf download.