SIST EN 3947:2001

Overview

SIST EN 3947:2001 is a European Standard developed by CEN that specifies the requirements for a specialized aerospace filler metal: Nickel base alloy NI-B15701 (NiPd34Au30) in the form of rolled foil. This standard defines the characteristics and quality criteria for the brazing filler metal used in high-performance aerospace applications, ensuring reliable joints and optimum performance under demanding conditions. The nickel-based alloy combines nickel with palladium and gold, providing excellent corrosion resistance, high-temperature stability, and mechanical strength, which are critical in aerospace manufacturing and repair processes.

Key Topics

• Alloy Composition: Defines the chemical makeup of the filler metal, highlighting the nickel base with specific percentages of palladium (Pd) and gold (Au) to achieve desired brazing properties.
• Form and Dimensions: Specifies that the filler metal is provided as rolled foil, which allows precise control over filler thickness and facilitates uniform brazing.
• Quality Requirements: Establishes criteria for purity, mechanical properties, and surface conditions to ensure consistent brazing performance.
• Brazing Applications: Focuses on use with aerospace components requiring high-strength, corrosion-resistant joints.
• Testing and Compliance: Includes guidance on testing methods and inspections to verify conformance with the standard.

Applications

SIST EN 3947:2001 is essential for aerospace manufacturers and maintenance providers involved with brazing of critical components such as:

• Turbine engine parts where heat and corrosion resistance are vital.
• Structural assemblies requiring strong, reliable brazed joints.
• Components exposed to extreme environmental conditions, including temperature fluctuations and mechanical stress.
• Repair and refurbishment processes for aircraft parts demanding alloy compatibility and controlled brazing filler characteristics.

Utilizing NI-B15701 (NiPd34Au30) rolled foil as defined in EN 3947 helps ensure enhanced joint integrity, prolonged component life, and adherence to stringent aerospace safety standards.

Related Standards

• Other Aerospace Filler Metals: Standards covering different nickel-base or cobalt-base filler metals for brazing in aerospace, to compare material properties and suitable applications.
• Brazing Process Standards: Documentation outlining recommended brazing procedures, temperature profiles, and inspection techniques to optimize joint quality.
• Material Handling and Testing Standards: Norms that govern storage, handling, and quality testing relevant to filler metals to maintain compliance and traceability.
• Corrosion and Mechanical Properties Standards: For assessing the performance of brazed joints under operational stresses typical in aerospace environments.

By aligning with SIST EN 3947:2001, aerospace industry professionals can ensure the consistent quality and performance of brazed components critical to flight safety and operational excellence.