Overview
ISO 14323:2015 - "Resistance welding - Destructive testing of welds - Specimen dimensions and procedure for impact tensile shear test and cross‑tension testing of resistance spot and embossed projection welds" - defines how to prepare and test specimens for destructive impact testing of resistance spot and embossed projection welds. The standard applies to overlapping metallic sheets with thicknesses from 0.5 mm to 4 mm, and covers specimen dimensions, test equipment, test procedures, energy/force measurement and reporting requirements for impact tensile shear and impact cross‑tension tests.
Key technical topics and requirements
- Scope and materials: Applicable to any metallic material with sheet thickness 0.5–4 mm for spot and embossed projection welds in overlap configuration.
- Specimen dimensions and accuracy: Specimen geometries are provided for three thickness ranges (0.5–1.5 mm, 1.5–3 mm, 3–4 mm). Weld positional accuracy on the specimen shall be ±1 mm or better.
- Minimum sample size: At least five specimens per test condition.
- Test machines and parameters:
- Modified pendulum machine (typically for 0.5–3 mm): U‑shaped hammer, pendulum impact velocity ≈ 5.5 m/s; force measured with strain gauges or load cells.
- Drop‑weight machine (typically for 1–4 mm): striker velocity 5–15 m/s; can be single or double striking type; instrumentation must record force/time and displacement/velocity.
- To ensure complete fracture, impact energy should be greater than 10× the failure energy.
- Failure energy determination: Annex A describes methods to calculate absorbed (failure) energy from force/time records - single integration (force/time), or double‑integration to derive force/displacement without direct displacement measurement.
- Test records and reporting: The standard specifies required report items (reference to ISO 14323, equipment, settings, welding process/conditions, material condition, specimen dimensions, individual and statistical results for impact strength and energy, weld diameter, failure mode descriptions, tester names, etc.).
Practical applications and who uses this standard
ISO 14323 is used by:
- Welding test laboratories and quality control teams to qualify spot and projection weld processes.
- Automotive, aerospace, appliance and general metal‑fabrication industries for weld performance validation, durability assessment, and supplier audits.
- R&D and materials engineers for comparative evaluation of materials, electrode designs and welding parameters.
- Certification bodies and OEMs that require standardized destructive testing methods for contract and compliance verification.
Using ISO 14323 helps ensure consistent, repeatable impact tensile shear and cross‑tension testing results for resistance welded joints - essential for product safety, process optimization and supplier qualification.
Related standards
- ISO 14272 - specimen dimensions and procedure for cross‑tension testing (normative reference).
- ISO 17677‑1 - resistance welding vocabulary (normative reference).