Evaluation of Ultrasonic Attenuation Methods and Surface Roughness of Binder Jet 316L Bronze Infused Stainless Steel
Open Access
- Author:
- Starr, Daniel
- Area of Honors:
- Engineering Science
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Andrea P. Arguelles, Thesis Supervisor
Gary L. Gray, Thesis Honors Advisor - Keywords:
- ultrasound
attenuation
reflection
binder jet
surface roughness - Abstract:
- Technical Additive manufacturing is a fabrication method that is rapidly growing across many industries. One form of additive manufacturing that possesses many advantages is Binder Jet Printing. With all its advantages, it is necessary to carefully evaluate the material characteristics before general adoption. In this work, Binder Jet printed metals will be examined through ultrasonic evaluation. Ultrasonic evaluation is nondestructive and possesses the ability to accurately examine samples for material characteristics as well detect defects within a medium. In this work, several ultrasonic methods to calculate attenuation and reflection coefficient presented theoretically in literature are employed to evaluate an as-printed sample with surface roughness. After ultrasonic testing, the sample is polished to mirror finish and the same ultrasonic measurements are then repeated. The reflection coefficient method, the EDC/Papadakis method, and the thickness independent wave speed and silica reference method were carefully evaluated. The reflection coefficient method was determined to be unreliable in both polished and unpolished trials. The EDC/Papadakis method proved to be promising at calculating attenuation and reflection of both smooth and rough samples, though. The silica reference method was found to agree well with the EDC/Papadakis method for the polished surface condition but overestimated the attenuation for the sample in its rough surface condition. Thus, this work established the preliminary knowledge needed to further investigate attenuation of rough samples by determining the validity and need to study various methods presented in the literature. Lay With the increasing popularity of additive manufacturing, this works seeks to evaluate the nondestructive characterization of binder jet printed metals. Three ultrasonic methods are used to evaluate a binder jet printed sample that exhibits substantial surface roughness. The three methods are each performed on the rough sample, then the sample is polished down to get ride of any roughness parameters. Once the sample is smooth, the same methods are then used again. The overarching goal is to evaluate and compare how each of the three methods perform both when the sample is rough, and when it is polished smooth.