SIST EN 2957:2020

Overview

SIST EN 2957:2020 is a European Standard published by CEN that specifies the method of preparation for forged test samples within the aerospace industry. It defines detailed requirements applicable primarily to round products with diameters of 20 mm or greater, as well as other shapes with equivalent cross-sectional areas. This standard ensures consistency and reliability in the production and testing of forged aerospace materials to meet stringent safety and quality criteria.

The standard is mandatory when referenced by relevant EN material standards or technical specifications, providing foundational guidelines for manufacturers and purchasers in aerospace sectors to agree upon sample preparation and testing procedures.

Key Topics

• Scope and Applicability
  SIST EN 2957:2020 applies to forged sample preparation for aerospace materials, focusing on round bars ≥ 20 mm in diameter or equivalent cross-sections. It is invoked by material-specific EN standards unless otherwise specified.

• Definitions

  • Blank: A sample cut from the forging stock.
  • Pancake: A sample obtained by upsetting (compressing) a blank.

• Blank Removal Method
  The location and size of blanks are agreed between purchaser and manufacturer unless otherwise indicated in technical specifications. The blank’s dimensions and forms are standardized based on forging stock diameter or cross-section to ensure representative sampling.

• Forging Conditions
  The forging temperature and heating regimen must be agreed upon, with blanks maintained at the target temperature for at least 30 minutes prior to forging. Final forging operations are preferably completed in one heat cycle. Pancake thickness should be one-third the original blank thickness.

• Use of Pancakes
  Pancakes serve multiple purposes in aerospace forging:

  • To assess forgeability of the material.
  • To evaluate structural characteristics against material standards or orders.
  • To provide specific locations for sampling mechanical test pieces such as impact or toughness tests, as indicated in the standard’s schematic figures.

Applications

SIST EN 2957:2020 is vital for aerospace manufacturers, quality assurance engineers, and material testing laboratories focused on structural components. It supports:

• Quality Control of Forgings: Establishing consistent sampling from forgings to verify mechanical properties and structural integrity.
• Material Certification: Assuring aerospace components meet EN material standards through standardized test samples.
• Process Optimization: Refining forging procedures and temperatures to produce reliable test pancakes representative of final products.
• Compliance and Traceability: Providing documented, standardized methods and dimensions that align with European aerospace regulations and quality assurance mandates.

Using this standard helps aerospace organizations reduce variability in testing samples, thereby improving reliability of mechanical tests and forging assessments critical to aviation safety and performance.

Related Standards

SIST EN 2957:2020 functions in conjunction with other EN material standards and technical specifications relevant to aerospace forgings, including but not limited to:

• EN material standards that reference forged products and specify mechanical testing requirements.
• Aerospace series standards developed by ASD-STAN (Aerospace and Defence Industries Association of Europe - Standardization).
• ISO and IEC terminology databases for harmonized definitions related to forged materials and testing.

Manufacturers and users of SIST EN 2957:2020 are advised to consult specific EN material standards applicable to their forged components for comprehensive requirements on testing and processing, ensuring full compliance with aerospace industry regulations.

Keywords: SIST EN 2957:2020, aerospace forging, forged samples preparation, aerospace standards, forged test samples, pancake sample, forging conditions, aerospace material testing, European aerospace standards, forged components quality control