A Line-Focus Transducer System for Property Characterization of Materials Fabricated by Additive Manufacturing

[摘要] Nondestructive evaluation methods have been studied increasingly in recent years. Due to its characteristics, such as high-resolution, low cost, etc., ultrasonic testing has become one of the most used NDE methods. Furthermore, principles of ultrasonic have also provided a novel tool for materials property characterization.A line-focus PVDF ultrasonic wave transducer was designed, fabricated, and tested.Numerous concepts of ultrasonic wave near boundary were discussed. Rayleigh (Surface) wave, which plays a vital role in this work, has been investigated and tested by the PVDF transducer. With tested Rayleigh wave velocities, elastic constant (Young’s Modulus) could be derived. Conclusions could be drawn through comparison since the relationship between elastic constants and Rayleigh wave was well studied.In addition to that, a short introduction of additive manufacturing was made briefly. Two additive manufacturing methods, laser-based and water-based were mentioned. Since properties of finished sample of additive manufacture still remain uncertainty. Samples fabricated in these two methods have been tested as well as standard part. The comparisons between these samples have been done in the end. The major goals of this work are to: 1) study the basic knowledge of Rayleigh wave properties and its applications; 2) develop an acoustic understanding of material fabricated in different methods; and 3) verify the relationship between elastic constants and surface wave velocity.

[发布机构] the University of Pittsburgh