短語詞組短語lack of side fusion 側面未熔合;側面未焊合lack of root fusion 根部未焊透lack of fusion in welds 焊縫中的未熔合inter -bead lack of fusion 焊道間未熔合lack of side wall fusion 側壁熔融不足lack of inter -run fusion 層間未熔合 返回 lack of fusion