短语词组短语lack of side fusion 侧面未熔合;侧面未焊合lack of root fusion 根部未焊透lack of fusion in welds 焊缝中的未熔合inter -bead lack of fusion 焊道间未熔合lack of side wall fusion 侧壁熔融不足lack of inter -run fusion 层间未熔合 返回 lack of fusion