Design and manufacturing optimization of epoxy-based adhesive specimens for multiaxial tests

Materials & Design

卷:212

Nikolas Manousides¹  Claudio Balzani²  Michael Wentingmann³  Alexandros Antoniou³ 

[1] Corresponding author.;

[2] Fraunhofer Institute for Wind Energy Systems IWES, Am Seedeich 45, 27572 Bremerhaven, Germany;

[3] Leibniz University Hannover, Institute for Wind Energy Systems, Appelstrasse 9A, 30167 Hannover, Germany;

关键词: Structural adhesives;    Multiaxial testing;    Porosity analysis;    Wind turbine rotor blades;   

DOI  :  

来源: DOAJ

【 摘 要 】

Specimen design and manufacturing quality are decisive factors in the experimental determination of material properties, because they can only be reliably determined if all undesired influences have been minimized or are precisely known. The manufacture of specimens from highly viscous, two-component and fiber-reinforced structural adhesives presents a challenge from this point of view. Therefore, a design and manufacturing optimization procedure for fiber-reinforced structural adhesives and multiaxial testing was developed. It incorporated a finite element parametric study to minimize stress concentrations in the specimen geometry. Vacuum speed mixing was combined with 3D printed mold inserts to enable the manufacture of homogeneous specimens with negligible porosity. The method was demonstrated by means of a structural adhesive used to manufacture wind turbine rotor blades, while the manufacturing quality was verified with high-resolution X-ray microscopy (μCT scanning), enabling detailed detection of pores and geometrical imperfections. The results of uniaxial and biaxial static tests show maximized strength and stiffness properties, while the scatter was minimized in comparison to that stated in international literature. A comparison of the mechanical properties and associated manufacturing techniques is given. The comparison includes a porosity analysis of a specimen from an industrial dosing machine used for rotor blade manufacture.

【 授权许可】

Unknown