3.2.3. Quality Evaluation of the Weld Bead

After orthogonal experimental design using chosen key operational parameters with different levels, for different experimental results, an accurate quantitative quality evaluation should be employed. In this work, the FCE method was introduced to quantitatively evaluate the quality of weld bead. Because this evaluation method can provide quantitative evaluation results based on some input conditions, and the quality of weld bead involves various different aspects including the appearance and shape, microstructure, and process stability of electrical signals, hardness and tensile performance, and so on, these quality criteria can be inputs of the FCE model using fuzzy mathematical algorithm, and then quantitative scores can be obtained.

FCE used the principle of fuzzy logic to evaluate the targets. There were two important procedures, the first was making evaluation using single element, while the second was making comprehensive evaluation using all elements. The detailed evaluation steps are shown in many published contributions [18,23,25]. In the next section, FCE can be employed in quantitatively estimating the quality of weld bead after orthogonal experiments.
