EN 3917:1998

Overview

EN 3917:1998 (adopted as SIST EN 3917:2001) is a CEN aerospace series standard that defines requirements for the nickel base alloy NI-B41201 (NiCr14Si5B3C) used as a filler metal for brazing in powder or paste form. The standard covers the identification and specification of this filler metal for aerospace applications, ensuring consistent quality and suitability for high-reliability joining processes in the aviation and space industries.

Key Topics

The standard addresses the main aspects relevant to a brazing filler metal specification without prescribing process parameters. Key topics typically covered include:

• Material identification and designation - formal name and alloy code (NI-B41201 / NiCr14Si5B3C).
• Product form and presentation - definitions for powder and paste forms used in brazing operations.
• Quality and conformity requirements - criteria for acceptance, supply conditions, and manufacturer responsibilities.
• Physical and chemical characteristics - classification by alloying elements (nickel, chromium, silicon, boron, carbon implied by the NiCr14Si5B3C designation) and general property expectations.
• Packaging, marking and documentation - labeling, traceability and accompanying certificates required for aerospace use.
• Intended application scope - limitations or recommendations relevant to aerospace brazing supply chains.

Note: EN 3917:1998 specifies requirements relating to the filler metal itself; brazing process parameters (heat source, joint design) are handled in process and qualification standards.

Applications

EN 3917:1998 is intended for contexts where reliable brazed joints are critical:

• Aerospace component manufacturing and repair - turbine parts, heat exchangers, exhaust systems and assemblies where nickel-based fillers are chosen for temperature and corrosion resistance.
• Aerospace suppliers of brazing consumables - producers of brazing powders and pastes who must meet aerospace quality standards.
• Quality assurance and procurement - specification and acceptance of filler metal deliveries for aerospace programs.

Using a standardized nickel filler metal helps ensure material compatibility, traceability and consistent performance in demanding aerospace environments.

Who Uses This Standard

• Aerospace OEMs and tier suppliers
• Brazing material manufacturers and distributors
• Welding and brazing engineers
• Quality and procurement teams in aviation and space sectors
• Certification and inspection bodies

Related Standards

For full implementation, users typically consult EN 3917:1998 together with other CEN aerospace and brazing process standards covering brazing methods, joint qualification, and inspection/acceptance criteria.

Keywords: EN 3917:1998, NI-B41201, NiCr14Si5B3C, nickel base alloy, filler metal for brazing, brazing powder, brazing paste, aerospace brazing, CEN.