Quality monitoring of aluminum alloy DPMIG welding based on broadband mode decomposition and MMC-FCH

•Broadband mode decomposition is proposed for decomposing broadband signals with “sharp corners”.•An associative dictionary library consisting of typical broadband signals and narrowband signals is constructed.•ACROA is adopted for determining the optimized parameter by using the smoothness function as the objective function.•BMD can effectively monitor the quality of aluminum alloy DPMIG welding combined with MMC-FCH.