Leichtbau

@article{Bartsch2023,

title = {Mechanical Properties of NdPrFeB Based Magnetoactive Bisphenol- Free Boron-Silicate Polymers},

author = {A. Bartsch and D. Beham and J. Gebhardt and I. Ehrlich and T. Schratzenstaller},

url = {https://www.walshmedicalmedia.com/open-access/mechanical-properties-of-ndprfeb-based-magnetoactive-bisphenolfree-boronsilicate-polymers-124385.html},

doi = {10.35248/2157-7439.23.14.705},

year  = {2023},

date = {2023-11-30},

urldate = {2023-11-30},

journal = {J Nanomed Nanotech},

issue = {14: 705},

abstract = {Following a ban on many materials containing bisphenol-A, new bisphenol-free Boron silicates have been found as substitutes. The purpose of this study is to describe the mechanical properties of these bisphenol-free magnetoactive borosilicate polymers containing hard magnetic particles. Samples of 0%, 33% and 66% by wt. were loaded for compression using a universal testing machine. The maximum forces occurring for different travel speeds were compared before and after post-magnetization treatments. The post-magnetization included 2 stages. In addition, the change in mechanical properties within 24 hours after the post-magnetization process was investigated. Furthermore, the influence of speed and particle content were investigated. In general, there is a correlation between the required compressive force and, the level of post-magnetization stress, the increase in travel speed and particle content in the boron silicate. Comparison of the non-post-magnetized and post-magnetized samples using two-tailed t-tests shows that the p-values for all weight fraction changes in NdPrFeB particles and travel speeds are less than 0.001. Also, a comparison between tests in which the traverse speed was varied also showed significant changes in the resulting compression forces. The same is valid for changes in the weight ratio of the NdPrFeB particles in the samples. For post-magnetized samples, no significant difference can be observed in the first 24 hours following magnetization. In summary, the material presents viscoelastic, plastic force-displacement behavior, which can be well recognized by its bi-linear curve shape. The investigation shows that borosilicate polymers based on NdPrFeB can have their mechanical behavior modified and controlled by post-magnetization processes. This opens new possibilities for many future applications.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GEBHARDT2023104663,

title = {Low-velocity impact behavior of elliptic curved composite structures},

author = {J. Gebhardt and M. Schlamp and I. Ehrlich and S. Hiermaier},

url = {https://www.sciencedirect.com/science/article/pii/S0734743X23001744},

doi = {https://doi.org/10.1016/j.ijimpeng.2023.104663},

issn = {0734-743X},

year  = {2023},

date = {2023-01-01},

urldate = {2023-01-01},

journal = {International Journal of Impact Engineering},

volume = {180},

pages = {104663},

abstract = {Although many composite structures are inconsistently curved, such as the leading edges of aircraft wings, the variety of research in impact engineering is almost limited to the impact performance of plates or cylindrically curved specimens. It is not known whether the findings obtained from standardized tests can be transferred to curved structures or which adaptions are required. Therefore, a deeper understanding of the deformation and damage behavior of inconsistently curved structures is essential to transfer the observed impact behavior of flat specimens to general curved structures and therefore to utilize the full lightweight potential of a load-specific design. An accurate description of the procedure as well as the results of the experimental and numerical study of the low-velocity impact behavior of differently single-curved elliptic specimens is presented. To close the research gap of the impact behavior of geometries with curvatures between the plates and simplified leading edges, novel specimens geometries have been derived from established impact test standards. Glassfiber-reinforced specimens are subjected to an instrumented impact test at constant impact energy. This is numerically investigated by a stacked-layer model, which used cohesive zone modeling to enable the simulation of matrix cracking, fiber fracture and delamination. The resulting projected damage areas, as well as the force and deflection histories, were evaluated and section cuts were examined to discuss the damage morphology, formation and propagation process. Significant effects on maximum deflection, compliance and dynamic behavior on the size and morphology of damage were found.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}