Rubber conveyor belts are an important part of the transport chain in many industries, ranging from food processing to steel mills. In this context, it is important to employ scrapers, which remove adhering goods from the belts and reduce loss of these resources during transport. The tribological contact between belt and scraper is of high importance as this often is a source of wear and unintended energy consumption. In this work, the interaction between scrapers and belt was investigated by utilizing a pin-on-disk setup with and without abrasive intermedia. A strong dependence of friction and wear on the alignment angle between pin and belt was proven by the investigations. An orthogonal setup caused the highest coefficient of friction, but the lowest wear, while an increasing deviation from the 90° alignment, resulted in an inverse trend. Also, the geometrical shape and size of the abrasive determined wear, as larger, sharper particles enhanced wear. Abrasive particles likewise influence the tribological contact between pin and belt by reducing the friction compared with the 2-body contact.

Impact loading is an important process in the transport industry as it causes wear and failure of critical components. Conveyor belts are of particular importance as they are used in practically every industry where large quantities of goods are moved over short (<10 m) or long distances (>1 km). To investigate stress levels inside the material during impact loading, a gas gun was utilized to shoot 9 mm spherical steel balls onto the surface of a rubber conveyor belt. A high speed video recording system was employed in order to determine penetration depth and dissipated energy of the steel ball. Maximal penetration depths of up to 3.9 mm and maximal dissipated energies of up to 86.8 % were measured. Additionally, a numerical simulation using smooth particle applied mechanics was conducted and compared to the experimental results obtained with the gas gun. The calculated von Mises stresses affected the conveyor belts up to a maximum depth of 8.8 mm with at least 20 MPa. Maximum von Mises stresses were calculated to reach 60 MPa.

Predicting the lifetime of a conveyor belt from lab-scale tests has become increasingly important, as the cost for the belt represents up to 70% of the acquisition and maintenance costs of a transport system. In practice, belt selection relies strongly on the well-established ISO 4649 abrasion test, where fixed corundum paper is utilised as the abrasive medium, resulting in 2-body abrasion. In the present article, this is compared to the ASTM G65 test with rolling, round abrasive particles, leading to 3-body abrasion. To evaluate the lab-scale results, they were compared to a conveyor belt that had been used to transport sintered charge for eight years. The comparability and reproducibility of wear patterns encountered on this particular belt was matched with the lab test and then correlated with mechanical properties of the rubber materials.It was found that the LSO 4649 tests, where abrasive wear is dominant rarely reflect wear patterns and wear mechanisms occurring in real applications. In contrast, the ASTIV1 G65 3-body abrasion test entails fatigue dominated wear, which is found in real applications. The ISO 4649 test results showed a strong dependence on tensile strength and Shore A hardness, while tear strength was the most influential factor for the ASTM G65 test. (C) 2014 Elsevier BA/. All rights reserved,

Controlling the morphology, electronic properties, and growth direction of nanowires (NWs) is an important aspect regarding their integration into devices on technologically relevant scales. Using the vapor-solid-solid (VSS) approach, with Ni as a catalyst and octachlorotrisilane (Si(3)Cl(8), OCTS) as a precursor, we achieved epitaxial growth of rectangular-shaped Si-NWs, which may have important implications for electronic mobility and light scattering in NW devices. The process parameters were adjusted to form cubic α-NiSi(2) particles which further act as the shaping element leading to prismatic Si-NWs. Along with the uncommon shape, also different crystallographic growth directions, namely, [100] and [110], were observed on the very same sample. The growth orientations were determined by analysis of the NWs' azimuths on the Si (111) substrates as well as by detailed transmission electron microscopy (TEM) and selected area electron diffraction (SAED) investigations.

The applicability of a novel silicon precursor with respect to reasonable nanowire (NW) growth rates, feasibility of epitaxial NW growth and versatility with respect to diverse catalysts was investigated. Epitaxial growth of Si-NWs was achieved using octochlorotrisilane (OCTS) as Si precursor and Au as catalyst. In contrast to the synthesis approach with SiCl(4) as precursor, OCTS provides Si without the addition of H(2). By optimizing the growth conditions, effective NW synthesis is shown for alternative catalysts, in particular, Cu, Ag, Ni, and Pt with the latter two being compatible to complementary metal-oxide-semiconductor technology. As for these catalysts, the growth temperatures are lower than the lowest liquid eutectic; we suggest that the catalyst particle is in the solid state during NW growth and that a solid-phase diffusion process, either in the bulk, on the surface, or both, must be responsible for NW nucleation.