Overview
ISO 17279-2:2018 - Welding: Micro joining of 2nd generation high temperature superconductors - Part 2 specifies the qualification requirements for personnel who perform micro-joining, oxygenation annealing, and subsequent testing of 2G HTS test joints. It is part of the ISO 17279 series and complements procedure requirements given in ISO 17279-1 and general qualification principles in ISO 15607. The standard ensures consistent, reproducible, and low-resistance autogenous joints in 2G high temperature superconductors (2G HTS).
Key topics and technical requirements
- Scope of qualification
- Defines who must be qualified: personnel performing micro-joining, oxygenation annealing, and testing of 2G HTS test joints.
- Manufacturers are responsible for training programs, written practice (WPS), examinations, and maintaining qualification records.
- Essential variables and ranges
- Joint design (lap or bridge), joint widths (examples: 3 mm, 4 mm, 6 mm, 12 mm or specified sizes).
- Superconducting materials (e.g., YBCO, GdBCO, SmBCO) and specific material dimensions.
- Apparatus: specific model/control systems; devices must be periodically calibrated and only calibrated equipment may be used for qualification.
- Micro-joining and oxygenation-annealing parameters: removal of Cu stabilizer/Ag overlayer, heating rates, peak joining temperature, mechanical pressure, dwell times, chamber vacuum/pressure, oxygen flow, and cooling rates.
- Qualification methods
- Standard test joint specimens produced per an approved WPS; three specimens tested per joint design; work witnessed by an inspector.
- Testing of test joints and documented examination reports required.
- Validity and re-qualification
- Initial qualification, periodic confirmation, and procedures for prolongation or re-qualification when essential variables change.
- Third-party check and annexes
- Provision for third-party checks; normative annexes cover required functional knowledge and technology, informative annexes supply data report formats, test-result examples, and checklists.
Practical applications and users
- Who uses this standard:
- Manufacturers of 2G HTS tapes and assemblies ensuring competent micro-joining operations.
- Welding and joining technicians and laboratories performing superconducting joints.
- Quality, inspection and testing personnel responsible for certifying joint performance.
- Training organizations preparing qualification programs and examinations.
- R&D teams developing joining processes for superconducting devices.
- Practical value:
- Standardizes personnel qualification for reliable, low-resistance superconducting joints.
- Reduces variability by defining essential variables, documented tests, and calibration requirements.
- Supports traceability through records, examination reports, and checklists useful for conformity and audit.
Related standards
- ISO 17279-1:2018 - General requirements for micro-joining procedures for 2G HTS.
- ISO 15607:2003 - Specification and qualification of welding procedures for metallic materials (general rules).
Keywords: ISO 17279-2:2018, 2G HTS, micro-joining, oxygenation annealing, personnel qualification, welding personnel, test joints, WPS, superconducting joints, qualification methods.
Open preview (PDF)Welding — Micro joining of 2nd generation high temperature superconductors — Part 2: Qualification for welding and testing personnel
