DIN 17850: Titanium and Titanium Alloys-General Requirements for Semi-Finished Products

Titanium and Titanium Alloys-General Requirements for Semi-Finished Products

DIN 17850 is a German industrial standard that defines the general technical delivery conditions for semi-finished titanium and titanium alloy products, including:

Rods

Bars

Wire

Tubes

Sheets

Plates

Forgings

It works as an umbrella standard, specifying common rules and testing requirements that apply across product-specific DIN standards like:

DIN 17860 (tubes)

DIN 17861 (bars, rods)

DIN 17862 (sheets, plates)

Applicable Product Forms

DIN 17850 applies to semi-finished titanium products such as:

Hot-rolled or cold-worked rod and bar

Forgings and forging stock

Seamless and welded tubes

Plates, sheets, and strips

Wire

Key Technical Requirements

1. Chemical Composition

Must conform to specific alloy standards (e.g., Ti Gr 1, Gr 2, TiAl6V4)

Chemical analysis required per DIN or EN test methods (e.g., spark OES, gas analysis)

2. Mechanical Properties

Determined by the product standard (e.g., DIN 17861, DIN 17862)

Properties such as:

Yield strength

Ultimate tensile strength

Elongation

Reduction of area

3. Heat Treatment

Supplied in defined conditions:

Annealed

Cold-worked

Solution-treated and aged

Heat treatment must be traceable by batch/lot

Surface Quality

Surfaces must be:

Free from cracks, oxide flakes, laps, burrs

Free from oil, grease, and heavy contamination

Light pickling or grinding is permitted to remove minor defects

Dimensional Tolerances

Tolerances not defined in DIN 17850 itself but set by:

Product-specific DIN standards

EN ISO standards (e.g., ISO 2768, ISO 286)

Customer specifications

Testing & Certification Requirements

Mechanical testing (tensile, bend, etc.) per batch

Non-destructive testing (NDT): May be required for critical products

Ultrasonic testing: On thick plate, forged bar, or aerospace materials

Surface inspection: Visual and tactile

Grain size and microstructure on request

Inspection documents:

3.1 or 3.2 certificates per EN 10204

Include:

Heat number

Chemical composition

Mechanical properties

Heat treatment

Dimensional verification

Marking

Each product must be marked with:

Manufacturer’s name or symbol

Material grade (e.g., Ti Grade 2)

Heat or batch number

Product dimensions

Standard (e.g., DIN 17850 / DIN 17861)

Relation to Other Standards