DIN 65079: Titanium and Titanium Alloys-Tubes

Titanium and Titanium Alloys – Tubes

This standard specifies the technical delivery conditions, dimensional tolerances, and mechanical properties for seamless titanium and titanium alloy tubes, primarily used in aerospace, high-performance industrial, and engineering applications.

It complements general titanium product standards like DIN 17850 and is used when higher precision or aerospace-grade requirements are necessary.

Product Forms Covered

Seamless round tubes

Produced by hot or cold working

Typically supplied in:

Annealed condition

Stress-relieved or solution-treated for alloys

Applicable Materials

The standard includes commercially pure titanium and titanium alloys, typically:

Other alloys (e.g., Ti-6Al-2Sn-4Zr-6Mo, Ti-15V-3Al-3Cr-3Sn) may be used depending on application.

Dimensional Tolerances (Typical)

* Final tolerances depend on alloy, condition, and manufacturing route.

Mechanical Properties

Tubes must meet specified minimum mechanical values according to the alloy and delivery condition.

Example for Ti Grade 2, annealed:

Yield strength         ≥ 275 MPa

Tensile strength≥ 345 MPa

Elongation≥ 20%

Grade 5 (Ti-6Al-4V) in solution-treated condition may require:

Yield Strength≥ 880 MPa

Tensile Strength ≥ 950 MPa

Elongation≥ 10%

Inspection & Testing

Required inspections include:

Chemical composition

Tensile testing

Dimensional check

Visual inspection

Optional tests (if specified or for aerospace use):

Eddy current testing

Ultrasonic inspection

Flattening / flaring test

Microstructure analysis

Hardness or grain size

Surface Condition

Tubes must be free of cracks, laps, oxide layers, and defects.

Pickled, polished, or ground finishes are common.

Internal and external surface finishes must meet aerospace or industrial specifications if required.

Marking and Certification

Each tube must be marked with:

Alloy type (e.g., Ti Gr 5)

Batch or heat number

Manufacturer’s identification

Standard reference (DIN 65079)

Delivery condition (e.g., annealed)

Inspection Certificate per EN 10204, typically 3.1 or 3.2 for aerospace.

Related Standards

DIN 17850: General requirements for titanium

DIN 17860: Titanium seamless tube (general industry)

ASTM B338: Seamless titanium tubes

ISO 13384: Titanium tubes for heat exchangers