Page 731 - จันทร์จืรา เดชแพง
P. 731

Probes












                      • Piezoelectric transducer





                                 – Lead zirconate titanate, Lead metaniobate, Barium




                                        titanate





                      • May be transmitter or receiver






                      • Variety of frequencies, crystal sizes & angles





                      • Normal probes






                                 – Longitudinal waves





                      • Angle probes





                                 – 45°, 60°, 70° in steel





                                 – Transverse waves
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