Steel rail flaw detection ultrasonic waveguide inclined probe and flaw detection method thereof

The invention discloses a steel rail flaw detection ultrasonic waveguide inclined probe and a flaw detection method thereof. The probe comprises a shell, a sound absorption filler, at least one dielectric unit and at least one interface, wherein each dielectric unit is arranged inside the shell and comprises a wedged block, a dielectric wafer, a cable wire and a damping block; the dielectric waferis a dielectric ceramic piece of a thickness vibration mode; an included angle is formed between one surface of the wedged block and the horizontal plane; one surface perpendicular to a vibration direction, of the dielectric wafer, is flatly adhered to the surface of the wedged block; the damping block is tightly adhered to another surface perpendicular to the vibration direction, of the dielectric wafer; the sound absorption filler is arranged inside a vacant space except the dielectric unit inside the shell; the interface is arranged on one surface of the shell and is connected with the dielectric wafer through the