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Pipes are mainly used in waste, drain and vent systems as well as transporting various liquids that might be corrosive, flammable, explosives, volatile, reactive, or sometimes hazardous to human health. Though pipes are used at the underground or above ground, all of them are exposed to vibration because of external factors. In this study, we focused on topology optimization of steel and PVC (Polyvinyl Chloride) pipes to get lighter ones which will lead to using less material during manufacturing, less CO2 emission while transporting them to usage areas by vehicles and easier assembling process. Firstly, new lightweight pipe designs were modeled, and then these novel pipe designs with lattice wall thickness were analyzed by using Ansys finite element program in clamped-free, hinged-hinged, and clamped-clamped boundary conditions to obtain the natural frequencies, mode shapes, and displacement values. Moreover, obtained finite element results for steel and PVC pipes were compared with analytical results calculated by using the equation to check and compare with the finite element results. Finite element results were found similar to analytical results at an acceptable level. The results show that lightweight pipes have similar natural frequency values to the commonly used pipe which has fully solid wall thickness and some significant results about displacement values were attained. Lastly, the effect of pipe material on vibration behaviors of pipes was investigated in depth. [ABSTRACT FROM AUTHOR]

Recently, coating applications of hard engineering ceramics on metallic alloys have become notably widespread in order to expand the service life of the critical design components working in though conditions like corrosive/oxidative or erosive/abrasive media. Even though scientific efforts on coating processes and their effects on wear and corrosion performance have been studied for years, there is a lack of investigation about mechanical properties, especially thermo-mechanical features of hard ceramic coated metals. In this paper, on the purpose of determination of the thermal stress distribution, effects of coating materials (Al2O3, AlN and TiB2) and coating thickness (400 µm, 600 µm, and 800 µm) on Von-Mises stress, shear stress and resultant displacement for single and full surface coating models designed on Ti-6Al-4V base material are investigated at 373 K, 573 K and 873 K. The results show that modulus of elasticity and thermal expansion coefficient of coating ceramic materials and base metallic material affect the elongation and stress values observed on designed models significantly. Besides, coating thickness and ambient temperature are also effective on thermal properties. Lastly, it can be pointed out that resultant displacement values on a singlesurface coating model are higher than full surface coating model. However, Von-Mises and shear stress values calculated with finite element analysis on single surface coating model is lower than the values read for fullsurface coating model. [ABSTRACT FROM AUTHOR]

Cutting with abrasive water jet is an effective method for many engineering materials. Owing to its ability providing close tolerances and dimensional accuracy as well as cutting of extremely hard materials, total using rate of abrasive water jet cutting (AWJC) in the industry rises day by day. In addition to cutting, turning of the many industrial materials can be turned into the practice with abrasive waterjet turning (AWJT) technology. In recent years, AWJC and AWJT become considerably popular cases in the machining of hybrid composite materials which consist of at least two unlike reinforcements and researches about this subject increase rapidly in order to elucidate process details and influences of input parameters. Water pressure, traverse speed, abrasive flow rate, standoff distance and abrasive particle mesh size are the most prominent parameters of the process. In this paper, abrasive waterjet cutting/turning applicability of hybrid composites was reviewed and an initiative was done to rake together the newest surveys published in the technical literature. Our purpose is to achieve detailed overview for AWJC/AWJT of hybrid composites and to emphasize feasibility of the AWJC/AWJT for them and to discuss future real application possibilities of the method. [ABSTRACT FROM AUTHOR]