24 research outputs found
Precision joining of steel-aluminum hybrid structure by clinching process
No full textAn innovative technology of clinching joining can reduce the
production costs, cycle times, and also offer prospective product design and
manufacturing. In this study, the overlap joining of low carbon steel and
aluminum alloy in clinching process was experimentally and numerically
investigated. The tensile-shear strength of overlap-clinched joints was
evaluated through tensile-shear test. This test was also used to study the
deformation and failure of clinched joints under tensile-shear loading. The
results showed that the higher press load had a great influence for achieving
better interlocking between steel-aluminum hybrid structures. Insufficient
interlocking and thin neck thickness led to the failure of clinched joints.
Moreover, the most critical region of the clinching tool was located at the
radius corner of punch and die
"Hallux limitus"
No full textIn the present work, the Author wants to break with that absurd Antagonism between M.I.S procedures and open or traditional Surgery. As much some procedures as the other have their Indications. In this case, according to himself criterion, it is from first election the procedure for open Surgery. Procedure that he explain very descriptivly.En el presente trabajo, el autor quiere romper con ese absurdo antagonismo entre procedimientos M.I.S. y por cirugía abierta o tradicional. Tanto unos procedimientos como los otros tienen sus indicaciones. En este caso, según criterio del mismo, es de primera elección el procedimiento por cirugía abierta. Procedimiento que expone muy descriptivamente
Precision Joining of Steel-Aluminum Hybrid Structure by Clinching Process
Get PDFClinching joining has become an alternative technique to conventional spot welding. This innovative joining technology can reduce the production costs and cycle times, and also offers a great prospective for a new product design and manufacturing. Without a better understanding on physical phenomena associated with the clinching process, the correcting unacceptable clinched joint is extremely costly and impossible for some cases. In this study, the overlap joining of low carbon steel and aluminum alloy in clinching process was experimentally and numerically investigated. The tensile-shear strength of overlap-clinched joints was evaluated by tensile-shear test. This test also was used to study the deformation and failure of clinched joints under tensile-shear loading. The results showed that the higher press load has a great influence for achieving better interlocking between steel-aluminum hybrid structures. Insufficient interlocking and thin neck thickness lead to the failure of clinched joints. It also was confirmed that the most critical region of the clinching tool located at the radius corner of punch and die. Development of simplified engineering approaches based on numerical simulation and correlations with experimental data could be very beneficial to industrial applications
An overview on robust design hybrid metamodeling: Advanced methodology in process optimization under uncertainty
No full textTrade-off in robustness, cost and performance by a multi-objective robust production optimization method
No full textCoastal protection Malecón seawall: A study to develop a sea defence solution that prevents unacceptable flooding and damage to the 'Malecón Tradicional' in Havana, Cuba
No full textThis report presents a study of the Malecón Tradicional in front of ‘Centro de Havana’ and ‘Havana Vieja’ in the city Havana, Cuba. The objective is to develop a sea defence solution that prevents unacceptable flooding of the hinterland and damage of the Malecón seawall. Implementing the recommended solutions reduces the overtopping sufficiently. Along the entire study area, it is recommended to raise the seawall and to construct a revetment. It was concluded that a curved wall is only useful in combination with a revetment for a small part of the seawall. Both the top part and the seaside face of the Malecón seawall need a structural fortification in order to withstand the design conditions. It is recommended to partly remove the top of the current wall and replace it with a new wall, which is extended in seaward direction. Both for the design storm and for the ultimate limit state, the proposed solution satisfies the strength requirements.Hydraulic EngineeringCivil Engineering and Geoscience
Corrosion Characterisation of Al-Cu Reinforced In-Situ TiB2
No full textAluminium (Al) based in-situ metal matrix composites (MMCs) have better properties and performance compared to ex-situ MMCs. In this research, aluminium-copper (Al-Cu) alloy was reinforced with 3 and 6wt.% titanium diboride (TiB2). Al-MMCs has been fabricated with salt route reaction process at 800 °C via potassium hexafluorotitanate (K2TiF6) and potassium tetrafluoroborate (KBF4) salts. Hardness vickers tester and Gamry-Electrod Potentiometer were used to characterize the hardness properties and to determine the corrosion rate of Al-Cu alloys. From results obtained, increased TiB2 contents will increase the hardness of Al-Cu alloys. Increased of TiB2 contents also will increase the corrosion rate of Al-Cu alloys. Al-Cu with 3wt.%TiB2 gave the good properties of corrosion when the wear rate recorded the lowest value compare to Al-Cu alloy itself and 6 wt.% TiB2. The corrosion rate of Al-Cu with 3wt.TiB2 was 16.15, while Al-Cu and Al-Cu-6wt%TiB2 were 22.5 and 58.7 mm/y respectively
Recent developments in metamodel based robust black-box simulation optimization: An overview
No full textIn the real world of engineering problems, in order to reduce optimization costs in physical processes, running simulation experiments in the format of computer codes have been conducted. It is desired to improve the validity of simulation-optimization results by attending the source of variability in the model’s output(s). Uncertainty can increase complexity and computational costs in Designing and Analyzing of Computer Experiments (DACE). In this state of the art review paper, a systematic qualitative and quantitative review is implemented among Metamodel Based Robust Simulation Optimization (MBRSO) for black-box and expensive simulation models under uncertainty. This context is focused on the management of uncertainty, particularly based on the Taguchi worldview on robust design and robust optimization methods in the class of dual response methodology when simulation optimization can be handled by surrogates. At the end, while both trends and gaps in the research field are highlighted, some suggestions for future research are directed
