kSIST FprEN 3160:2025

Overview

The prEN 3160:2024 standard, developed by CEN and ASD-STAN, specifies the stringent requirements for steel grade X5CrNiCu17-4 (1.4542) bars intended for aerospace applications. These steel bars are air melted, solution treated, and precipitation treated, available with diameters or cross-sectional dimensions (a or D) up to 200 mm. This standard ensures a minimum tensile strength (Rm) of 1,310 MPa, making it ideal for critical aerospace components requiring high strength and reliability.

The document updates and supersedes the earlier EN 3160:2007, enhancing steel designation accuracy, test procedures, and technical specifications in line with aerospace industry demands. It aligns with EN 4258 and EN 4500 series standards to ensure material consistency, quality, and traceability in aerospace manufacturing.

Key Topics

• Material Composition:
  Steel X5CrNiCu17-4 is a chromium-nickel-copper stainless steel alloy with controlled carbon (max 0.07%), silicon, manganese, phosphorus, sulfur, chromium (15.0–17.5%), nickel (3.0–5.0%), copper (3.0–5.0%), and niobium/tantalum content. This composition is optimized for corrosion resistance and mechanical strength.

• Melting and Heat Treatment:
  The steel must be air melted followed by solution treatment at 1025–1055 °C for at least 30 minutes with air cooling, and optionally precipitation treatment between 470–490 °C for a minimum of 1 hour to enhance mechanical properties.

• Mechanical Properties:
  The standard mandates a minimum tensile strength (Rm) of 1,310 MPa and a yield strength (Rp0.2) of at least 1,170 MPa. Elongation and reduction of area properties are clearly defined depending on bar dimension ranges to guarantee ductility and toughness.

• Dimensions and Forms:
  Bars covered by the standard have a cross-section or diameter up to 200 mm, accommodating a broad range of aerospace structural and mechanical component sizes.

• Testing and Inspection:
  The standard requires compliance with various testing methods, including:

  • Chemical composition verification,
  • Microstructure analysis (δ-ferrite content ≤ 5%),
  • Visual inspection for external defects,
  • Ultrasonic testing for internal imperfections,
  • Verification of mechanical properties according to EN 4700-002.

• Documentation and Traceability:
  Marking, dimensional inspection, and product qualification procedures ensure traceability and fulfillment of quality assurance protocols.

Applications

Steel X5CrNiCu17-4 bars specified by prEN 3160:2024 are utilized in critical aerospace applications where high strength and corrosion resistance are essential. Typical uses include:

• Structural components in aircraft and spacecraft,
• High-stress mechanical parts such as shafts, rods, and fasteners,
• Engine components subject to challenging thermal and mechanical environments,
• Aerospace manufacturing where adherence to precise material standards is mandatory.

Owing to its excellent combination of mechanical strength and corrosion resistance, this steel is preferred for parts that demand reliability under cyclic loads and exposure to varying environmental conditions.

Related Standards

prEN 3160:2024 is part of a comprehensive series of metallic material standards for aerospace applications. Related standards include:

• EN 4258 – General organization of aerospace metallic material standardization, providing framework and classification.
• EN 4500-005 – Rules for drafting and presentation of material standards specific to steels.
• EN 2043 – General requirements for qualification of semi-finished aerospace metallic products.
• EN 4700-002 – Technical specifications and testing methods for wrought steel bars.
• EN 4436 – Methods for determining δ-ferrite content in steel.

Compliance with these interconnected standards ensures material integrity, performance, and international acceptance in the aerospace sector.

By adhering to prEN 3160:2024, aerospace manufacturers and suppliers can guarantee the highest quality and performance of steel X5CrNiCu17-4 bars, meeting the stringent demands of modern aerospace engineering. This standard supports the production of safer, more durable aerospace components while facilitating global regulatory compliance and material traceability.