Ultrasonic sensor signals and optimum path forest classifier for the microstructural characterization of thermally-aged inconel 625 alloy

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Victor Hugo C. de Albuquerque (Author) Other; Cleisson V. Barbosa (Author) Other; Cleiton C. Silva (Author) Other; Elineudo P. Moura (Author) Other; Pedro P. Rebouças Filho (Author) Other; João P. Papa (Author) Other; João Manuel R. S. Tavares (Author) FEUP

Journal

Title: Sensors

Vol. 15 No. 6

Pages: 12474-12497

ISSN: 1424-3210

Publisher: MDPI

Indexing

ISI Web of Knowledge - 17 Citations

ISI Web of Science

Scopus - 19 Citations

INSPEC

Scientific classification

FOS: Engineering and technology

CORDIS: Technological sciences

Other information

Authenticus ID: P-00G-B1X

DOI: 10.3390/s150612474

Abstract (EN): Secondary phases, such as laves and carbides, are formed during the final solidification stages of nickel-based superalloy coatings deposited during the gas tungsten arc welding cold wire process. However, when aged at high temperatures, other phases can precipitate in the microstructure, like the ¿ 00 and ¿ phases. This work presents an evaluation of the powerful optimum path forest (OPF) classifier configured with six distance functions to classify background echo and backscattered ultrasonic signals from samples of the inconel 625 superalloy thermally aged at 650 and 950 ¿C for 10, 100 and 200 h. The background echo and backscattered ultrasonic signals were acquired using transducers with frequencies of 4 and 5 MHz. The potentiality of ultrasonic sensor signals combined with the OPF to characterize the microstructures of an inconel 625 thermally aged and in the as-welded condition were confirmed by the results. The experimental results revealed that the OPF classifier is sufficiently fast (classification total time of 0.316 ms) and accurate (accuracy of 88.75% and harmonic mean of 89.52) for the application proposed.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 24