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The Quality Assurance of Cast and Wrought Aero Jet Engine Components Made from Ni-base Superalloys with Using of Quantitative Metallography Methods and Alloys Lifetime Prediction

Abstract

The Ni-base superalloys are used in the aircraft industry for the production of aero engine most stressed parts, turbine blades or turbine discs. Quality of aero jet engine components has a significant influence on the overall lifetime of a jet engine as itself as well as the whole airplane. From this reason a dendrite arm spacing, grain size, morphology, number and value of γ′-phase are very important structural characteristics for blade or discs lifetime prediction. The methods of quantitative metallography are very often used for evaluation of structural characteristics mentioned above. The high-temperature effect on structural characteristics and application of quantitative methods evaluation are presented in this paper. The two different groups of Ni-base alloys have been used as experimental material: cast alloys ZhS6K and IN713LC, which are used for small turbine blades production and wrought alloys EI 698VD and EI 929, which are used for turbine disc production. Selected alloys have been evaluated in the starting stage and after applied heat-treatment at 850°C for 24 hrs. This applied heat-treatment causes structural changes in all alloys groups. In cast alloy dendritic structure is degraded and gamma prime average size has grown what has a negative influence on turbine blade creep rupture life. Wrought alloys show partially grain boundary melting and grain size changed due to recrystallization what causes mechanical properties decreasing – ultimate tensile strength mainly.

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Multiaxial Fatigue Experimental Analysis of 6063-T66 Aluminum Alloy of the Base Material and the Welded Material

., Riboli, M., Spagnoli, A., 2018, Full-model multiaxial fatigue life calculations with different criteria , Procedia Engineering, 213, 126-136, DOI: 10.1016/j.proeng.20118.02.014 Uhríčik, M., Kopas, P., Palček, P., 2015, Experimental and numerical analysis of aluminium alloy fatigue lifetime under combined cyclic bending-torsion loading , 32 th International Colloquium – Advanced manufacturing and repair Technologies in vehicle industry, Svojanov, Czech republic, 45-52. Yu, Z.-Y., Zhu, S.-P., liu, Q., Liu, Y., 2017, Multiaxial fatigue damage parameter and

Open access
Local Corrosion of AISI 304 Stainless Steel in Acidic Chloride Solution

., Oravcová, M., Palček, P., Sapieta, M., Chalupová, M., 2016. The stress detection and the fatigue lifetime of stainless steel AISI 316L during three-point bending cyclic loading. (Conference Paper) EAN 2016 - 54th International Conference on Experimental Stress Analysis. www.italinox.sk (15.03.2019). Zatkalíková, V., Markovičová, L., Belan, J., Liptáková, T., 2014. Variability of local corrosion attack morphology of AISI 316Ti stainless steel in aggressive chloride environment. Manufacturing Technology, 14, 3, 493–497.

Open access
Promoting Sustainable and Circular Plastics Use in Egipt with Implementation of Ecodesign Principles

Abstract

Green Supply chain, Green Packaging, Eco-labels, and Eco-design strategies are concepts that are discussed frequently within scientific and political debates. Eco-design strategies for Lifecycle Design include the Eco-design Strategy wheel which presents eight Eco-design strategies: New concept development, Selection of low-impact materials, Reduction of materials usage, Optimization of production techniques, Optimization of distribution system, Reduction of impact during use, Optimization of initial lifetime, and Optimization of end-of-life system. This research investigates specifically the selection of low impact raw materials phase using the European Union as a benchmark to improve the Egyptian situation and aims to apply the closed loop cycle to the Egyptian Plastics Industry. Its goal is to enlight the way towards Sustainable and Circular economy system in Plastics manufacturing sector in Egypt while emphasizing the financial benefits from the Business and Marketing perspectives rather than the Environmental perspective only.

Open access
Fatigue Characteristics of Materials Used in Transport Industry Applications

Abstract

Designers have a major interest about fatigue properties of materials used in transport industry. Each component in transport works under alternating stress. From this point of view the fatigue properties are important for single parts lifetime resulting into safety of whole components as cars and airplanes what leads to safety on the roads or air and have influence on human life as well. Therefore this paper deals with fatigue properties of wrought Inconel alloy IN 718 and aluminum cast alloy AlSi9Cu3. Both materials were put on fatigue push – pull test, but Ni – based IN 718 alloy at frequency of loading around 20 000 kHz (High Frequency High Cycles Fatigue) and aluminum alloy AlSi9Cu3 at frequency of loading around 80 Hz (Low Frequency High Cycles Fatigue). These parameters were chosen with respect of usage such materials for production of components used in transport industry applications. Results after fatigue tests are presented as Wohler curve. For prediction of source of fracture the SEM fractography analysis of fatigue fracture surfaces was made.

Open access