Overview
EN ISO 14273:2016 - Resistance welding: destructive testing of welds - specifies specimen dimensions and a testing procedure for tensile shear testing of resistance spot and embossed projection welds. It applies to overlapping metallic sheets with thicknesses from 0.5 mm to 10 mm, and welds with a maximum diameter of 7√t (t in mm). The main objective is to determine the tensile shear strength (TSS) - the maximum tensile shear force a specimen can sustain.
Key topics and technical requirements
- Specimen dimensions and sampling
- Specimen geometry and sampling positions are defined (see Table 1 and Figure 1 in the standard). Table values target the saturated strength condition (e.g., for t = 0.5–1.5 mm: overlap ≈ 35 mm, specimen width ≈ 45 mm; larger thicknesses have proportionally larger specimens).
- For weld diameters between 5√t and 7√t, Annex A warns that standard specimen sizes can underestimate TSS; minimum coupon width of 7–10× weld diameter is recommended for saturated conditions.
- Test equipment and procedure
- Use a tensile testing machine complying with ISO 7500-1 (force-measuring verification).
- Test at room temperature; plot a load–displacement curve to capture deformation and failure behavior.
- For sheet thickness > 3 mm or thickness ratio > 1.4, shim plates are required for clamping.
- Force measurement accuracy: ≤ ±1%.
- Results and reporting
- Record individual TSS values, mean, standard deviation, weld diameters and failure modes (symmetrical/asymmetrical plug, interfacial failure, etc.).
- Required test report information includes welding process, conditions, material, specimen dimensions, statistical results and special remarks.
Applications
- Used for quality control, weld development, material qualification and comparative evaluation of spot welds and embossed projection welds in automotive, aerospace, appliance and general sheet-metal fabrication.
- Supports suppliers and manufacturers in verifying joint strength, validating welding parameters, and documenting destructive testing results for contracts and inspection.
Who uses this standard
- Welding engineers, QA/QC inspectors, metallurgical labs, production engineers, and R&D teams involved in resistance welding, joint testing and product certification.
Related standards
- ISO 7500-1 - Verification of static uniaxial testing machines (tension/compression).
- ISO 17677-1 - Resistance welding vocabulary (spot, projection and seam welding).
- Use together with industry-specific welding and material standards when specifying test regimes.
Keywords: Resistance welding, tensile shear testing, spot welds, projection welds, embossed projection welds, specimen dimensions, tensile shear strength, EN ISO 14273:2016, destructive testing.
