Overview
CEN ISO/TR 20174:2020 (ISO/TR 20174:2020) is a technical report that defines a Japanese grouping system for materials used in welding and related processes. Prepared by ISO/TC 44 in collaboration with CEN/TC 121, this second edition (2020) supersedes the 2005 edition and maps Japanese JIS material designations to the grouping framework of ISO/TR 15608. The report covers standardized steels, aluminium and aluminium alloys, and titanium and titanium alloys and is intended for classification for welding purposes and other processes such as heat treatment, forming, and non‑destructive testing.
Key topics
- Material grouping methodology: Classification follows the grouping system of ISO/TR 15608:2017, enabling consistent categorization for welding applications.
- Steels (Table 1): Comprehensive listing of JIS G steel grades (structural steels, plates, sheets, high‑strength steels, stainless steels, carbon steels, etc.) mapped into ISO/TR 15608 groups.
- Aluminium and alloys (Table 2): JIS H aluminium alloy numbers mapped to ISO grouping for welding use.
- Titanium and alloys (Table 5): JIS titanium materials referenced against ISO grouping (document includes these listings).
- Scope of application: While focused on welding, the grouping is explicitly applicable to heat treatment, forming, non‑destructive testing, and related material selection activities.
- Document characteristics: This technical report contains tables of JIS designations mapped to ISO groups; there are no normative references or formal term/definition lists in the report.
Applications and users
CEN ISO/TR 20174:2020 is practical for professionals and organizations needing clear cross‑referencing between Japanese standards and international grouping systems:
- Welding engineers and procedure developers - for selecting compatible filler metals and approving welding procedures (WPS).
- Materials and metallurgical engineers - for material classification, heat‑treatment planning and forming considerations.
- Quality, inspection and NDT personnel - to link inspection requirements and acceptance criteria to material groups.
- Manufacturers and fabricators - especially those sourcing or specifying JIS‑specified steels, aluminium, or titanium for international projects.
- Suppliers of welding consumables - to match consumables to grouped material classes.
- Procurement and standards teams - for contract specifications that require consistent international material identification.
Related standards
- ISO/TR 15608:2017 - grouping system used as the classification basis.
- JIS standards (e.g., JIS G and JIS H series) - source designations for steel and aluminium grades.
- ISO/TC 44 and CEN/TC 121 publications on welding and allied processes.
Keywords: ISO/TR 20174:2020, welding grouping systems, Japanese materials, JIS material classification, ISO/TR 15608, steels, aluminium alloys, titanium alloys, welding consumables, material grouping.