Theair-based　1-3　piezoelectric　composite　transducers　are　designed　and　fabricated　in　order　to　solve　the　acoustic　impedance　matching　problem.　Firstly,　a　finite　element　model　using　honeycomb　structure　as　the　piezoelectric　composite　matrix　is　built　to　reduce　the　acoustic　impedance　of　the　sensitive　element.　Three　important　factors,　volume　fraction　of　piezoelectric　materials　phi,　the　thickness　h,　and　the　size..　of　the　square　cross　section　of　piezoelectric　column,　are　examined　and　verified　in　simulation.　Then,　according　to　the　result　of　simulation,　the　piezoelectric　composites　and　the　air-coupled　transducers　are　fabricated.　The　honeycomb　structures　of　resin　are　produced　by　the　method　of　3D　printing　technology,　with　the　volume　fraction　of　air　being　30%.　The　impedance　characteristics　and　the　excitation/reception　performance　of　the　air-coupled　transducers　are　measured　and　optimized.　Meanwhile,　a　scanning　experiment　is　carried　out　to　demonstrate　the　crack　detection　process　inmonocrystalline　silicon.　A(0)　mode　of　Lamb　waves　is　excited　and　collected.　The　location　and　size　of　the　defect　will　be　determined　by　calculating　the　correlation　coefficients　of　the　received　signals　and　reference　signals.　Finally,　a　15　mm　x　0.5　mm　x　0.5　mm　scratch　is　clearly　distinguished.