EN 3355:2012

Overview

EN 3355:2012 - Aerospace series - defines material and delivery requirements for titanium alloy TI-P64001 (Ti‑6Al‑4V) in annealed, extruded sections with external diameter De ≤ 150 mm and high tensile strength (Rm between 900 MPa and 1 160 MPa). Published by CEN/ASD-STAN, this standard is part of the EN metallic materials series for aerospace applications and sets chemical, mechanical, heat‑treatment and testing references for purchasers and manufacturers.

Key topics and technical requirements

• Material designation: TI‑P64001 (Ti‑6Al‑4V).
• Chemical composition: Aluminium and vanadium are controlled (Al ≈ 5.50–6.75%, V ≈ 3.50–4.50%); limits for interstitials and impurities (O, N, Fe, C) are specified in the standard.
• Form and production: Extruded sections produced by α+β or β processing; maximum external dimension De ≤ 150 mm.
• Delivery condition: Annealed. Typical anneal: 690 °C – 840 °C, t ≥ 30 min, air cooled or cooled in inert atmosphere. Delivery condition code: U (per EN 2032‑2).
• Mechanical properties:
  • Tensile strength Rm: 900 – 1 160 MPa
  • Proof stress Rp0,2: ≥ 830 MPa
  • Elongation A: ≥ 8%
  • Reduction of area Z: ≥ 20%
• Testing and inspection: Specifies referencing EN 4800‑002 for sampling, dimensional checks, visual/internal defect criteria, microstructure, marking and inspection procedures.
• Additional heat‑treatment note: If post‑anneal straightening or stretching is done below 550 °C, a stress relief at 550–700 °C / ≥ 30 min is required.

Applications and practical value

EN 3355:2012 is intended for the aerospace supply chain where high strength‑to‑weight titanium extrusions are required. Typical uses include structural components and assemblies where certified Ti‑6Al‑4V extruded sections are specified. Practical benefits:

• Ensures consistent mechanical performance and traceability for aerospace parts.
• Provides clear acceptance criteria (chemical, mechanical, dimensional, inspection).
• Streamlines procurement and quality assurance between manufacturers and purchasers.

Who should use this standard

• Aerospace materials engineers and designers specifying metallic materials.
• Manufacturers and mill producers of titanium extrusions.
• Procurement specialists and purchasing authorities in aerospace OEMs and suppliers.
• Testing laboratories and quality/control inspectors responsible for material qualification and acceptance.

Related standards

• EN 4800‑002 (Titanium - Technical specification - Bar and section)
• EN 4258 (Organisation of aerospace metallic material standards)
• EN 4500‑4 (Rules for drafting titanium material standards)
• EN 2032‑2 (Coding of metallurgical delivery condition)

EN 3355:2012 is a targeted material standard for Ti‑6Al‑4V extruded, annealed sections used in aerospace - essential for consistent supply, testing and regulatory compliance.