China 
Africa 
Explore chapters and articles related to this topic
Friction Stir Welding (FSW) and Friction Stir Spot Welding of Dissimilar Sheet Materials
Published in Kakandikar Ganesh Marotrao, Anupam Agrawal, D. Ravi Kumar, Metal Forming Processes, 2023
Sukanta Das, R. Ganesh Narayanan
Adhesive bonding is not recommended because of its long curing and bonding cycles and its affinity towards the moisture content in the environment. The moisture can degrade the strength of the joint to a large extent. Mechanical fasteners like rivets, bolts, and screws. The main limitation of using mechanical fasteners is that the hole prepared to place the fasteners generates stress concentration. Solid welding processes are found to be more efficient in joining aluminium and polymer. Ultrasonic welding is used only to spot weld the aluminium and polymer. Ultrasonic spot-welding tooling and machines are not that cost-effective, which hinders the use of this joining process. The limitation with friction welding is that it always required a flat surface and high tooling and machine costs [136].
Power Screws, Fasteners, and Connections
Published in Ansel C. Ugural, Youngjin Chung, Errol A. Ugural, Mechanical Engineering Design, 2020
Ansel C. Ugural, Youngjin Chung, Errol A. Ugural
The success or failure of a design can depend on the proper selection and use of its fasteners. A fastener is a device to connect or join two or more members. Many varieties of fasteners are available commercially. The threaded fasteners are used to fasten the various parts of an assembly together. We limit our consideration to detachable threaded fasteners such as bolts, nuts, and screws (Figure 15.1). General information for threaded fasteners as well as for other methods of joining is presented in some references listed at the end of this chapter, and at the websites www.americanfastener.com and www.machinedesign.com. Listings of a variety of nuts, bolts, and washers are found at www.nutty.com. For bolted joint technology, see the website at www.boltscience.com.
Design for Disassembly
Published in Anoop Desai, Anil Mital, Sustainable Product Design and Development, 2020
If possible, product design should incorporate the least variety of fasteners possible. Examples of fasteners include screws, nuts, bolts rivets and so on. The larger the variety of fasteners used in a product, the more the need for an equally greater variety of tools to disassemble them, skills to access and remove the fastener, surface preparation for disassembly and working postures necessary for achieving the disassembly process.
Experimental and numerical study on vibration and structure-borne noise of composite box-girder railway bridges
Published in International Journal of Rail Transportation, 2022
Xiao Liu, Nan Zhang, Qikai Sun, Zhaozhi Wu
The bridge vibration response and structure-borne noise can be evaluated by loading the force transferred to the bridge into the bridge model. The obtained fastener force is applied to the corresponding position of the fastener on the bridge deck according to the nodal force loading mode. The numerical simulation results are compared with the test results for points V1, V2, V3, S1, S2, and S3. The vibration comparison results are presented in Figures 8(a), 8(c), and 8(e). The overall trend exhibits that the test results rationally agree with the numerical results. Due to the complexity of the actual structure of the SCC box girder, some simplifications are made in modelling the engineering problem, such as omitting some longitudinal stiffeners and connecting plates with smaller structural sizes. For the case of high-frequency vibration, the average vibration energy of the plate subsystem is taken into account, thus yielding the deviation of the simulation results. The comparative analysis results of the noise measurement points are presented in Figures 8(b), 8(d), and 8(f), and the measured results of the three test points are in good agreement with the predicted results by the numerical simulation. The measured and computed peak frequency of sound pressure of S1~S3 is between 40 Hz and 80 Hz, and the deviation is small. It is proved that the vibration and noise calculation method proposed in the present work has specific reliability and accuracy.
Inverse identification method of adhesive creep properties from real scale investigations on bonded fastener
Published in The Journal of Adhesion, 2022
Marthe Loiseau, Sylvain Chataigner, Romain Créac’hcadec, Jean-Philippe Court, Marie-Odette Quéméré
The analysis of the stress field in the adhesive highlights that the normal stress is not homogeneous along the fastener due to the non-uniform adhesive thickness and the fastener geometry (Figure 10). It can be checked that the fastener thickness profile effectively reduces the stress concentration on the edge. Moreover, Figure 10 highlights that stress is concentrated in the middle of the adhesive layer (from 0 to 0.4 of the normalised distance from the centre of the adhesive. Furthermore, the state of stress is not constant over time (Figure 10). Indeed, Figure 10 shows the normal stress S22 in the centre of the adhesive layer at different moments of the creep test. Yet, it shows that almost instantly (before , where is the time to failure of the creep test) the normal stress S22 does not evolve during the rest of the creep test. Consequently, the normal stress S22 does not evolve during more than 99% of the creep test. The state of stress could thus be considered constant over time for this geometry.
Use of impressed current for accelerated corrosion testing of aluminium alloy panels
Published in Corrosion Engineering, Science and Technology, 2022
Mahdi Jokar, Joshua T. Boerstler, G. S. Frankel
In this work, impressed anodic current was used to assess the impact on corrosion of coated AA7075-T6 panels with a stainless steel 316 (SS316) fastener. The scribed panels were subjected to an applied current from the fastener while they were exposed to continuous or intermittent ASTM B117 salt spray conditions. By applying a current between the fastener and panel, the coating degradation can be studied under more controlled conditions than by simple galvanic interaction between the fastener and panel. Furthermore, because the magnitude of applied current was controlled by the galvanostat, these tests could be conducted at accelerated rates compared to test panels that rely on galvanic interaction. This technique was also used to determine the effect of chromate conversion coating (CCC) and PreKote surface pre-treatments on corrosion morphology and measured current response during salt spray/dry and salt spray/dry/humid cycling.