QTL-mapping of individual resistance against American foulbrood in haploid honeybee drone larvae (Apis mellifera)

American foulbrood (AFB) is a severe brood disease in honeybees. Since sustainable treatment is not available, selection of genetically resistant honeybee stock is highly desirable. Using a set of 291 heterozygous microsatellite markers in a bulk segregant analysis with subsequent finemapping of haploid drone offspring from a single honeybee queen, we identified one significant and three suggestive quantitative trait loci as well as one significant epistatic interaction influencing prepupal survival after AFB infection. While we were not able to verify specific genes responsible for tolerance, we suggest that developmental genes may have played an important role. The identified markers can be used as regions of interest in future mapping or expression studies. In order to use them for markerassisted selection in breeding programmes for AFB-resistant honeybee stock, it will be required to evaluate these loci more extensively under variable experimental conditions.European Commission through the 6th framework collaborative Specific Targeted Research Project BEE SHOP (Bees in Europe and Sustainable Honey Production; EU contract number: FOOD-CT-2006-022568) and by the German Ministry for Education and Science (BMBF) through the FUGATO-plus project FUGAPIS (Functional genome analysis of disease resistance in honeybees, Apis mellifera; project number: 0315125A).http://link.springer.com/journal/135922015-07-31hb201

Hot stamping of load adjusted structural parts

The importance of high-strength steel concepts for car bodies has increased in recent years due to the necessity of weight reduction and improved crash safety. By using hot stamping or also known as press hardening of boron alloyed heat-treatable steels, it is possible to produce parts with a much higher strength than by cold forming processes. Depending on the stress profile of a structural part, it might be desirable to have different material rigidity in the part, with some high strength and other more ductile areas, so called "Tailored properties". There are a variety of methods to produce such parts, but all of these methods have currently still major challenges. Two methods to manufacture parts with tailored properties, these challenges and corresponding approaches are presented in this paper. This is on the one hand subsequently cooling in a spray field, which currently is still in the development phase because of challenges related to distortion. And on the other hand, the masked austenitization, which is used by only a few manufacturers due to the lack of experience, the impairments of coating condition and the great demands on the process management concerning re-cooling of the mask. Both variants are forward-looking and deliver high potential for further research.DFG/1691/11-2DFG/CRC/48

Heated gripper concept to optimize heat transfer of fiber-reinforced-thermoplastics in automated thermoforming processes

Today composite materials become increasingly more common to use for lightweight applications. This paper introduces a simulation approach for a handling and forming process. This process focusses on the robot based gripping, handling and forming of continuous-fiber-reinforced-thermoplastics, such as organo-sheet. The results of this paper show a manufacturing study of the heat transfer of a temperature-elevated organo-sheet during handling using heated needlegripper. Beside the fabric deformation, this research focuses on the temperature distribution during forming. Fast temperature drops lead to an increasing stiffness of the thermoplastic. Therefore, it is necessary to consider changing material parameters due to the temperature change. © 2019 The Author(s)

Local Heat Treatment in Draw Bending for Profiles of Manganese Boron Steel 22MnB5

Due to the increasing demand for vehicles with a low fuel consumption and consequently low emissions, lightweight construction is an important task in the automotive industry. High-strength profile parts reduce the total weight of the vehicle while maintaining a high bending-resistance. Draw bending combined with inductive sheet heating and subsequent cooling represents a cost-effective and economic concept for producing partially hardened profiles for small batch sizes. This paper deals with experimental investigations to optimize and examine heating and cooling in the process chain of draw bending. After designing the process by numerical simulation, the existing draw bending machine of the IFUM was expanded by an inductive heating unit and a cooling system. Subsequently, new experiments on the implementation of a heat treatment during draw bending were carried out with this machine. In the course of these experiments, the determined process limits were recorded based on the required drawing force, the temperature courses in the process and the respective hardness values. These values served to evaluate and validate the results of the numerical simulation. By means of heating the material before it enters the forming die, it could be shown that it is possible to form super high-strength-profile components through draw bending. The material was heated up to austenitization temperature by a surface inductor and cooled by the draw bending tool and the additional air cooling. The material used was the uncoated manganese-boron steel 22MnB5. Good results with regard to process and part quality were obtained by means of an upstream heating. The comparison with the simulation also showed a high degree of similarity and consequently confirmed the results of the numerical representation of the process. Thus the general feasibility of integrating a heat-treatment into a draw bending operation was successfully proved.DFG/BE 1691/146-

Attention, An Interactive Display Is Running! Integrating Interactive Public Display Within Urban Dis(At)tractors

Display or interaction blindness is a known problem for interactive public displays where passers-by simply ignore or pay little attention to them. While previous research created interventions that tried to address this problem or reported on differences between experiences in the lab and in the real world, little attention has been given to examining different attractors surrounding the interactive public display, i.e., people, artifacts, and stimuli that compete for people’s attention in the urban settings and distract them from interacting with public displays. This paper reports on a systematic examination of attractors around a case study of an interactive urban display in London. We outline the initial spatial exploration with the aim to identify suitable locations for the placement of the interactive public display within the urban setting, followed by a two-hour observation of attractors and stimuli around the urban display. We highlight the main attractors that compete for people’s attention and distract them from potentially interacting with the public display. We also note our attempt to reflect the environment and integrate the public display within its setting

Forming and Joining of Carbon-Fiber-Reinforced Thermoplastics and Sheet Metal in One Step

The processing and component properties of metals have led to their worldwide success in mechanical engineering. Their advantages are high ductility, efficient production methods, good joining ability and nearly isotropic mechanical properties. Fiber-reinforced plastics (FRP) are known for an excellent lightweight design potential, due to low density as well as high and anisotropic tensile stiffness. By using thermoplastics instead of thermoset matrices, processing times and therefore component costs have already been reduced significantly and thus have become affordable in large-scale application. If the advantages of both, metal and FRP, are intelligently combined, a part with tailored properties is created. However, suitable forming processes, which take the different forming effects of both materials into account, have to be developed yet. The scope of this research was to enable the combined forming, joining and impregnation of pre-impregnated FRP-sheets and sheet metal to steel-CFRP-steel-sandwich-parts in one process step. As forming and joining must be executed at temperatures above the melting point of the thermoplastic while the part removal must take place beneath this temperature, a heating concept for drawing tools was developed to enable short production cycles. In order to ensure an economic industrial production a fast heating and cooling of the tool is essential. Afterwards optimal impregnation and joining process parameters for short cycle times were determined with planar samplings. The influence of the process parameters on part quality was investigated microscopically. Based on this research, a forming tool was constructed and hat profiles of steel-FRP-steel sandwiches were drawn successfully. Subsequently, the impregnation quality was investigated based on the process parameter tool temperature. Furthermore, the geometrical deviation of formed hat profiles was investigated. © 2017 The Authors.European Research Association for Sheet Metal Working (EFB)German Federation of Industrial Research Associations (AiF)Federal Ministry of Economic Affairs and Energy (BMWi

The Effect of Co Incorporation on the CO Oxidation Activity of LaFe1−xCoxO3 Perovskites

Perovskite oxides are versatile materials due to their wide variety of compositions of- fering promising catalytic properties, especially in oxidation reactions. In the presented study, LaFe1−xCoxO3 perovskites were synthesized by hydroxycarbonate precursor co-precipitation and thermal decomposition thereof. Precursor and calcined materials were studied by scanning electron microscopy (SEM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), thermogravimetric analysis (TG), and X-ray powder diffraction (XRD). The calcined catalysts were in addition studied by transmission electron microscopy (TEM) and N2 physisorption. The obtained perovskites were applied as catalysts in transient CO oxidation, and in operando studies of CO oxidation in diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). A pronounced increase in activity was already observed by incorporating 5% cobalt into the structure, which contin- ued, though not linearly, at higher loadings. This could be most likely due to the enhanced redox properties as inferred by H2-temperature programmed reduction (H2-TPR). Catalysts with higher Co contents showing higher activities suffered less from surface deactivation related to carbonate poisoning. Despite the similarity in the crystalline structures upon Co incorporation, we observed a different promotion or suppression of various carbonate-related bands, which could indicate different surface properties of the catalysts, subsequently resulting in the observed non-linear CO oxidation activity trend at higher Co contents

Experimental and numerical analysis of the flow behaviour of magnesium wrought alloy AZ31 for deep drawing processes at elevated temperatures

In the present paper, the flow behaviour of the magnesium wrought alloy AZ31 is analysed experimentally and numerically. Especial in deep drawing processes is the knowledge of the flow behaviour important. Depending on the type and size of the hardening and softening of a material, the process parameters such as temperature and sheet thickness must be adjusted to produce a flawless part. The material behaviour of magnesium is different compared to conventional steels, because the hardening and softening effects are changing highly with increasing temperature. For this purpose, yield curves were recorded experimentally at different temperatures by means of layer compression tests. Following the yield curves were converted based on the principle of the plastic work equivalence for finite element simulations (FEA). For validation, numerical simulations of the layer compression test at elevated temperature using the converted yield curve were carried out

Automated Stamp Forming of Continuous Fiber Reinforced Thermoplastics for Complex Shell Geometries

This research describes the development of a fully automated forming process of continuous FRP to assemble a down scaled battery tray for a plug-in-hybrid automobile. The paper presents the results of forming experiments and a restraint approach to avoid wrinkling, an FEM forming simulation to detect the wrinkling behavior, shear effects and temperature trajectories for the consolidation at the end of the forming step, and a multi material gripper-system used for handling and preforming. The gripper system is capable of handling continuous FRP in different states and features a pneumatic stamp to pre-drape the heated organic sheet.BMBF/Open Hybrid LabFactor

Wear Behavior of MoS2 Lubricant Layers during Sheet Metal Forming

The increased use of high and ultra-high strength steel and materials with a high adhesion tendency leads to higher demands regarding the wear resistance of forming tools. A promising approach addressing both challenges is to apply MoS2 dry film lubricant coating systems to the tool surface. These coatings reduce friction and the use of drawing oils and can also be used as an abherent. Once these coatings are exhausted, they can be chemically removed and reapplied. However, the tool life of the coatings cannot be predicted properly, due to their inhomogeneous wear behavior which depends on the forming parameters and differs locally. Moreover, there are carryover effects of MoS2-particles to already ablated areas. Given the unpredictability of the wear of dry film lubricant coatings, it is not possible to plan the recoating cycles appropriately and thus, the potential of these coatings for commercial applications is limited. In this research, the wear behavior of MoS2-layers in deep drawing processes was investigated on a test stand with DP800+Z coil material which ensures realistic load conditions at the draw ring radius. Firstly, the wear pattern was determined and locally different contact pressures were recorded and assigned to respective wear areas. Due to bending effects of the sheet material, there are two major areas of wear on the draw ring radius. During wear tests, the wear-dependent coating thickness during wear initiation was determined by using 3D laser scanning microscopy and the friction force was evaluated. © 2017 The Authors.European Research Association for Sheet Metal Working (EFB)German Federation of Industrial Research Associations (AiF)Federal Ministry of Economic Affairs and Energy (BMWi