GB/T 39167-2020 in English

Interpretation of the core content of the standard

This standard modification adopts the ISO 14273:2016 international standard, focusing on standardizing the tensile shear test method for resistance spot welding and projection welding lap joints. The main technological breakthroughs are reflected in:

Key technical requirements

1. Specimen size specifications

Strict classification based on the relationship between weld diameter and plate thickness (t):

• Conventional specimens: When the weld diameter is ≤5t, the dimensions shall be as specified in Table 1 (e.g., width is 80mm when t=2mm)
• Special specimens: When the weld diameter is 5t-7t, the width shall be 7-10 times the weld diameter (see Appendix C)

2. Fracture form determination

Implementation suggestions

Key points for equipment selection

The testing machine must meet the Class 1 accuracy requirements of GB/T 16825.1, and for samples with thickness＞3mm, equal thickness gaskets must be configured (Figure 4).

Data recording specifications

Mandatory requirements for recording: maximum shear force (±1% accuracy), statistical values of weld spot diameter (including standard deviation), and fracture form classification (Clause 7.2).

Analysis of Standard Evolution

Compared with the 2002 version of the industry standard, the 2020 version has the following major advances:

1. Introduction of the concept of saturation strength condition (Clause 3.3)
2. Increase of the geometric tolerance requirements of solder joints (±1mm)
3. Detailed description of shunt compensation for multi-solder joint specimens (Clause 5.2.3)