Development of a Multi-Station Creep Machine for Adhesive Joint Testing

• Type: Article in International Scientific Journal
• Date: 2022

Authors

Bezerra, GN (Author) Other; António Mendes Lopes (Author) FEUP; Da Silva, CMSM (Author) Other; da Silva, LFM (Author) FEUP; Nunes, PDP (Author) Other; Marques, EAS (Author) FEUP; Ricardo Carbas (Author) FEUP

Journal

Title: Journal of Testing and Evaluation

Vol. 50

Pages: 2382-2399

ISSN: 0090-3973

Publisher: American Society for Testing and Materials

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 1 Citation

Other information

Authenticus ID: P-00W-DB4

DOI: 10.1520/jte20210730

Abstract (EN): Adhesive joints have unique advantages when compared to conventional mechanical joints. Adhesives can undergo creep deformation at room temperature (cold flow) as well as at low stress (well below the yield point of the material), which can lead to considerable reduction in the life expectancy of the bonded structures. Therefore, performing creep tests to determine a material's expected behavior under certain operational or environmental conditions is of cru-cial importance. Available commercial creep machines are often designed to test a wide variety of materials and, thus, present suboptimal features for testing specimens with specific char-acteristics, as is the case of adhesive joints. In this article, a new multi-station creep test ma-chine is proposed and its main subsystems are described, namely the mechanical structure, the pneumatic servo-controlled actuation, the data acquisition, and the command software. The machine is able to run tests at a constant load that can be set from 100 up to 2,800 N, at intervals of 5 N, and a maximum displacement of 250 mm. The three stations can accommo-date single lap joints or bulk specimens and allow for totally independent and simultaneous tests, at temperatures ranging from -100 degrees C up to 200 degrees C. The measurement resolution for load and displacement is 0.025 N and 0.025 mm, respectively. Experimental results of creep tests are presented, and the multi-station creep machine behavior is validated by comparison to a reference equipment. The creep machine reveals good performance, with force and displace-ment repeatability below close to 6 N and 0.25 mm, respectively.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 18