Publications by authors named "Philipp WeiSSgraeber"

Introduction: Subtalar joint arthrodesis is primarily indicated for advanced osteoarthritis, hindfoot deformity, and/or instability. During the first 6-10 weeks after surgery, there is an intermediary structurally weaker state before complete bony fusion of the calcaneus and talus occurs. Loading of the foot can lead to mechanical stresses and relative movements in the former joint gap, which can impede the fusion process.

View Article and Find Full Text PDF

When porous materials are subjected to compressive loads, localized failure chains, commonly termed anticracks, can occur and cause large-scale structural failure. Similar to tensile and shear cracks, the resistance to anticrack growth is governed by fracture toughness. Yet, nothing is known about the mixed-mode fracture toughness for highly porous materials subjected to shear and compression.

View Article and Find Full Text PDF

The adhesion of pressure-sensitive adhesives (PSAs) is a complex phenomenon that can be understood through the characterization of different properties, including viscoelastic, mechanical, and fracture properties. The aim of the present paper is to determine the viscoelastic behaviour of an acrylic PSA and place it in the viscoelastic window, as well as to determine the tensile strength of the material. Additionally, different numbers of stacked adhesive layers and two crosshead speeds were applied to characterize the tensile strength of the adhesive in the different conditions.

View Article and Find Full Text PDF

In the present paper, an exploratory study on the creep behavior of a pressure sensitive adhesive (PSA) is performed. After the determination of the quasi-static behavior of the adhesive for bulk specimens and single lap joints (SLJ), SLJs were subjected to creep tests at 80%, 60%, and 30% of their respective failure load. It was verified that the durability of the joints increases under static creep conditions as the load level decreases, with the second phase of the creep curve becoming more pronounced, where the strain rate is close to zero.

View Article and Find Full Text PDF

The aim of this work is to analyze the difference between silicone/composite and silicone/metal interphases, both in terms of water diffusion behavior and failure of the aged joints. For that, silicone joints with two different suhbstrates were prepared. The substrates were polybutylene terephthalate with 30% of short glass fiber (PBT-GF30) and 6082-T6 aluminum.

View Article and Find Full Text PDF

Short fiber reinforced polymers are widely used in the construction of electronic housings, where they are often exposed to harsh environmental conditions. The main purpose of this work is the in-depth study and characterization of the water uptake behavior of PBT-GF30 (polybutylene terephthalate with 30% of short glass fiber)as well as its consequent effect on the mechanical properties of the material. Further analysis was conducted to determine at which temperature range PBT-GF30 starts experiencing chemical changes.

View Article and Find Full Text PDF