According to the non-linear character of voltage signal during aluminum alloy spot welding, the nugget quality is quantitatively described by using the Box Counting Dimension as the characteristic parameter for the first time.

• 摘要针对铝合金点焊过程中电压信号的非线性特点，从分形理论出发，首次尝试利用盒维数作为特征量对点焊质量进行定量描述。