【摘要】 针对电磁超声SAFT成像旁瓣重、主瓣宽导致微小缺陷定量失真的问题，提出一种基于相干因子（CF）加权的高分辨成像算法。在明确SH0导波长距传输特性的基础上，引入CF作为非线性滤波器进行自适应降噪。实验表明，CF加权有效遏制了主瓣展宽并剥离背景杂波，使缺陷能量斑高度收束。该算法显著降低了尺寸评估误差，实现了板壳结构早期损伤的高精度检测。更多还原

【Abstract】 To address the sizing distortion of micro-defects caused by high side lobes and broad main lobes in electromagnetic acoustic transducer(EMAT) SAFT imaging, a high-resolution imaging algorithm based on coherence factor(CF) weighting is proposed. Based on the characterization of the long-range propagation properties of the SH0 wave, the CF is introduced as a nonlinear filter for adaptive noise reduction. Experimental results demonstrate that CF weighting effectively suppresses main lobe broadening and eliminates background clutter, resulting in a highly concentrated defect energy spot. Consequently, this method significantly reduces the defect sizing error, achieving high-precision detection of early-stage damage in plate and shell structures.更多还原