SIST EN ISO 2626:1998

Overview

SIST EN ISO 2626:1998 specifies the hydrogen embrittlement test for copper, particularly focusing on deoxidized and oxygen-free high-conductivity copper grades. Developed by the International Organization for Standardization (ISO) under the designation ISO 2626:1973, this standard outlines a reliable method to assess the susceptibility of copper materials to embrittlement when exposed to hydrogen atmospheres. Embrittlement detection is achieved through close bending, reverse bending, or microscopic examination of test pieces. The standard ensures consistency and accuracy in identifying hydrogen-induced defects, supporting material quality and performance in critical applications.

Key Topics

• Hydrogen embrittlement in copper: The standard focuses on the tendency of deoxidized and oxygen-free copper to lose ductility and become brittle after exposure to hydrogen.
• Applicable copper types: Tests are conducted on high-conductivity coppers, including those that are deoxidized or oxygen-free, commonly used in electrical and industrial sectors.
• Test principles: Specifies heating the test piece in a hydrogen-rich atmosphere and subsequent cooling, either in the furnace atmosphere or by water quenching.
• Test pieces: Guidelines are provided for sample preparation, including close-bend and reverse bend specimens, ensuring inclusion of the original surface and attention to thickness and edge smoothness.
• Test procedures:
  • Close-bend test: Involves bending the copper sample to a specified angle at ambient temperature followed by inspection for cracks.
  • Reverse bend test: Utilizes standard wire reverse bending techniques (as per ISO 2625) to detect embrittlement.
  • Microscopic examination: Sectioned and polished samples are inspected at 200x magnification for signs of gassing or open grain structures indicative of embrittlement.
• Detection methods: Visual inspection and microscopic analysis to reveal the presence and extent of hydrogen embrittlement.

Applications

This standard is valuable across industries where copper and copper alloys are exposed to hydrogen, including:

• Electrical and electronics manufacturing: Ensures high-conductivity copper components are free from hydrogen-induced brittleness, which can impact performance and reliability.
• Power generation and transmission: Vital for busbars, wiring, and connectors subject to hydrogen atmospheres, helping prevent unexpected failures.
• Chemical processing and piping: Applies to copper pipework and fittings in hydrogen-rich processes.
• Material quality control: Routine testing according to ISO 2626 supports manufacturers and quality assurance laboratories in evaluating copper's fitness for demanding environments.
• Research and development: Provides a globally recognized procedure for studying copper embrittlement, supporting improvements in material design and processing.

By following the outlined procedures, companies can effectively identify compromised materials, reduce risk, and comply with international quality standards.

Related Standards

For comprehensive material assessment, consider referencing the following related standards:

• ISO 2625: Copper and copper alloys - Reverse bend testing of wire
• ISO/R 398: Bend test for copper and copper alloys
• EN ISO 2626: European adaptation of ISO 2626, aligned with SIST EN ISO 2626:1998
• Standards on copper purity, material properties, and mechanical testing within the ICS 77.120.30 sector

Adhering to SIST EN ISO 2626:1998 not only ensures material reliability but also helps organizations meet international compliance requirements in the use of copper and copper alloy products exposed to hydrogen environments.