SIST EN 2786:2008

Aerospace series - Electrolytic silver plating of fasteners

This standard specifies the electrolytic silver plating of fasteners used in aerospace applications.
It shall apply whenever referenced.

Luft- und Raumfahrt - Elektrolytisches Versilbern von Verbindungselementen

Diese Norm legt das elektrolytische Versilbern von Verbindungselementen für die Luft- und Raumfahrt fest.
Sie muss immer angewendet werden, wenn auf sie verwiesen wird.

Série aérospatiale - Argentage électrolytique des éléments de fixation

Aeronavtika - Elektrolitska posrebritev veznih elementov

General Information

• Status: Published
• Publication Date: 07-Apr-2008
• ICS: 49.030.01 - Fasteners in general
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 27-Mar-2008
• Due Date: 01-Jun-2008
• Completion Date: 08-Apr-2008
• Ref Project: EN 2786:2008 - Aerospace series - Electrolytic silver plating of fasteners

Overview

EN 2786:2008 - Aerospace series - Electrolytic silver plating of fasteners (CEN) defines the requirements for electrolytic silver plating of fasteners used in aerospace applications. The standard’s primary purpose is to prevent galling or seizure of mating parts by specifying preparation, plating procedure, post‑treatments and inspection criteria. EN 2786:2008 applies whenever it is referenced on product drawings or procurement documents.

Key topics and technical requirements

• Purpose: Prevent galling/seizure of aerospace fasteners through controlled silver plating.
• Surface preparation: Clean chemically/electrolytically with minimal abrasion, erosion or pitting. Avoid treatments that may produce hydrogen embrittlement. Optional etching (e.g., ferric chloride / hydrochloric acid) may be used to promote adhesion.
• Plating process: Silver shall be deposited electrolytically over a suitable nickel and/or silver strike by an approved method. Plating thickness is specified in the relevant product standard or definition document. After plating, parts must be thoroughly rinsed and dried.
• Composition: Plated silver shall be not less than 99.9% pure; process control must ensure this purity.
• Appearance: Plate must be sound, smooth, uniform in colour and free from blisters and major imperfections. Minor abrasion on corners/threads and marking from locking features is acceptable; plating must remain continuous on threads.
• Post‑treatment / de‑embrittlement: Mandatory for martensitic steels with tensile strength > 1 100 MPa. De‑embrittlement must be performed as soon as possible, and no later than 16 hours after plating. Verification can be by EN 2831 / EN 2832 tests or a 200 h axial‑load dwell test (75% of tensile strength) with no fracture before 200 h.
• Adhesion testing: Heat parts in air to the applicable maximum test temperature (±8 °C) for ≥2 hours, cool in still air, then visually examine at 10× magnification. Blisters ≥0.38 mm are unacceptable. Follow with an adhesion test (EN 2828, EN 2830 or agreed method).
• Inspection classification: Acceptance tests per lot - appearance, thickness and adhesion. Periodic tests - composition and post‑treatments. A lot is defined by size/shape/alloy/thickness/solution batch within 24 hours.
• Quality assurance: Conformity with aerospace quality systems (see EN 9100).

Applications and who uses it

EN 2786 is used by:

• Aerospace fastener manufacturers and plating subcontractors
• OEMs, maintenance organizations and supply chain quality managers
• Procurement engineers specifying plating on drawings and purchase orders
• Metallurgists and process engineers controlling plating baths and hydrogen embrittlement mitigation

Practical applications include plating bolts, nuts, rivets and other fastening hardware where electrolytic silver plating is required to improve wear behaviour, reduce galling and ensure reliable mechanical performance in aerospace assemblies.

Related standards

• EN 2828 - Adhesion test by burnishing
• EN 2830 - Adhesion test by shearing action
• EN 2831 / EN 2832 - Hydrogen embrittlement tests (slow bending / notched specimen)
• EN 9100 - Aerospace quality management systems

Keywords: EN 2786:2008, electrolytic silver plating, aerospace fasteners, silver plating standard, hydrogen embrittlement, de‑embrittlement, adhesion testing, quality assurance.

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Aerospace series - Electrolytic silver plating of fastenersAeronavtika - Elektrolitska posrebritev veznih elementovSérie aérospatiale - Argentage électrolytique des éléments de fixationLuft- und Raumfahrt - Elektrolytisches Versilbern von VerbindungselementenTa slovenski standard je istoveten z:EN 2786:2008SIST EN 2786:2008en49.030.01ICS:SLOVENSKI
STANDARDSIST EN 2786:200801-junij-2008

EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 2786March 2008ICS 49.030.01 English VersionAerospace series - Electrolytic silver plating of fastenersSérie aérospatiale - Argentage électrolytique des élémentsde fixationLuft- und Raumfahrt - Elektrolytisches Versilbern vonVerbindungselementenThis European Standard was approved by CEN on 12 December 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2008 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 2786:2008: E
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