Development Of Ultrasonic Testing Technology For Narrow-Pulse

With the development and expand of modern industry, coarse-grain materials which have excellent comprehensive performance has more and more applications in defense, aerospace, nuclear power and other fields. Coarse-grain materials, because of its micro-structure characteristics, are very strongly on the scattering of ultrasonic, make serious noises and attenuation to ultrasound signals. This results to low sensitivity and signal to noise ratio (SNR) in ultrasonic testing of coarse-grain materials. Now it is still a difficult problem to test coarse-grain materials.This article key point for the development of Narrow-Pulse probe used for NDT and influence rule which produces the frequency shift and. The prime task is:Has determined the essential data which the experiment needs, had determined Epoxy resin thickener system and the tungsten powder quality allocated proportion, has drawn up probe production process, Dual function which match through the high impedance back lining and the electric circuit, may obtain the more ideal narrow pulse probe. Has determined the back lining, the match circuit to the different frequency PZT plate's influence, Discovered that the chip receives the back lining, electric circuit's influence to be small, when chip's frequency is low. The opposite experiment which carries on to the different frequency probe indicated that along with probe frequency's increase, its crack detection sensitivity reduces gradually, namely the low frequency probe's crack detection performance surpasses the high frequency probe.Indicated with the domestic and foreign homogeneous probe head crosswise contrast result that self-made narrow pulse performance parameters like probe head's pulse width, pulse periodicity must surpass domestically produced the commercial probe, but still had some disparity with the overseas advanced probe. How to further reduce the pulse duration enhances key point of the probe head sensitivity is next step works.