Ultrasonic detection device with coupling agent smearing function and using method thereof

The invention discloses an ultrasonic detection device with a coupling agent smearing function and a using method thereof. The device comprises a rack, a phased array ultrasonic probe and a smearing mechanism, wherein the rack comprises a first clamping block, a second clamping block and a wedge block, a cavity with an opening in the bottom end is formed between the first clamping block and the wedge block, the smearing mechanism comprises a coupling agent storage barrel, an extraction assembly used for extracting a coupling agent and a brush arranged in the cavity, and a liquid level sensor is installed in the coupling agent storage barrel. The device is simple in structure. The method comprises the steps of 1, installing a phased array ultrasonic probe and a liquid level sensor; 2, injecting a coupling agent into the coupling agent storage barrel; 3, placing the rack on the detection surface of a to-be-detected layered metal composite plate; and 4, smearing a coupling agent and carrying out phased array ult