EN ISO 9017 Destructive Tests on Welds in Metallic Materials - Fracture Test

EN ISO 9017, "Destructive testing of welds in metallic materials - Fracture testing," based on a European standard and subsequently published by the International Organization for Standardization (ISO), describes the dimensions of test specimens and procedures for performing fracture tests to obtain information on the types, sizes, and distribution of internal defects such as porosity, cracks, lack of fusion, lack of penetration, and solid inclusions on the fracture surface. This standard applies to metallic materials in all product forms with joints made by any fusion welding process with a thickness of 2 mm or greater.

For the purposes of this standard, the following terms and definitions apply:

• Inspection length is the length of the test specimen measured along the weld axis between any side notches.
• The total inspection length is the sum of the lengths of all test specimens constituting the test piece, measured along the weld axis of the fracture surfaces between the side notches of the test specimens.
• The inspection thickness is the thickness of the fracture area for each test specimen.
• The inspection area is the product of the inspection length and inspection thickness for each test specimen.
• The total inspection area is the sum of all inspection areas.

The joint is fractured along the weld metal to examine the fracture surface. Fracture can be induced by bending or tension, static or dynamic loading. Furthermore, notch dimensions and temperature can be varied to induce fracture. Testing should be conducted at ambient temperature (23°C plus/minus 5°C) unless otherwise specified.

Unless otherwise specified in the application standard or by agreement between the contracting parties, the test piece dimensions shall conform to the figures given in the standard. The test piece shall provide sufficient test specimen for the required total inspection length and area.

The inspection length, area, and number of test specimens are specified by the application standard or by agreement between the contracting parties. Welded joints in plates are cut transversely to the welded joint on test specimens of approximately equal weld length. For butt welds, the weld axis lies in the center of the test specimen. For welded joints in pipes, unless otherwise specified in the application standard or by agreement between the contracting parties, the test piece must provide at least two test specimens. When performing outward bend tests, an equal number of specimens are tested in root tension and surface tension. If the pipe diameter is too small to produce the required number of test specimens, additional test pieces must be welded.

Each test piece should be marked to identify its exact location in the manufactured product or joint from which it was removed. Each test specimen should be marked as it is removed from the test piece.

The removal method should prevent the occurrence of detrimental thermal or mechanical effects. In general, a 25 mm section should be removed from each end of the test welds unless information on the ends of the welds is required (e.g., start/stop defects).

Test specimens must be cut by thermal cutting or mechanical means. Other metallic materials can only be cut mechanically.

Fracture of welds in plates or pipes may be supported by one or more of the following:

• Removal of resource reinforcement
• Notching both edges of the weld (side notching)
• Notching into the reinforcement (longitudinal notching).

Depending on the ductility of the weld metal, square, round, or sharp notches can be used. For materials with high ductility (e.g., aluminum and copper), sharp notches are recommended. The notch depth should be sufficient to cause fracture in the weld.

The EN ISO 9017 standard is essential because it provides a standardized method for destructive testing of welds, particularly fracture and rupture testing. The main reasons for its importance are:

• Ensures weld quality: This standard describes how to perform and evaluate fracture tests to check:
  • Internal and surface defects in bend welds (e.g. cracks, porosity, lack of fusion)
  • Consistency and quality of weld material and its fusion with the base metal.

This helps verify whether the welds meet the required mechanical and structural standards.

• Provides objective criteria: Provides a uniform evaluation method as follows:
  • It explains how to prepare the sample, perform the test, and interpret the results.
  • Uses visual inspection of fracture surfaces as a reliable indicator of weld integrity.
• Supports compliance and certification: Manufacturers must comply with quality standards such as ISO 3834 Quality requirements for fusion welding of metallic materials and EN 1090 Production of steel and aluminum structures. EN ISO 9017 supports compliance with broader standards by ensuring that weld inspection methods align with international expectations.
• Facilitates cross-border communication: Because it's an international standard, it ensures global supply chain consistency. It also reduces misunderstandings about source quality among manufacturers, inspectors, and customers.
• Promotes safety and reliability: Welds are often found in critical structural components (e.g., buildings, bridges, pipelines). Fracture testing according to EN ISO 9017 ensures:
  • Defects are detected before failure
  • The structure remains safe under load and in service

In short, the EN ISO 9017 standard is necessary to ensure consistent, objective and internationally recognised quality control for fillet welds through destructive testing.

Our organization, which has been supporting businesses across all sectors for years through a wide range of testing, measurement, analysis, and evaluation activities, has a strong team of employees who closely follow global developments in science and technology and are constantly improving themselves. In this context, we also provide testing services in accordance with the EN ISO 9017 "Destructive testing on welds in metallic materials - Fracture testing" standard.