Search

Knowledge of the residual stress magnitudes induced during the manufacturing process is of interest since these could affect the structural integrity of manufactured parts depending on whether these are in tension or compression. It is also well known that in a wide variety of aerospace components subjected to external loads during work service, only the compressive residual stresses are acceptable. Therefore, the aim of this work focuses on determining residual stresses and their effects created along aluminum parts manufactured by single point incremental sheet forming (SPIF) process. Experimentally, the residual stresses induced during the SPIF process of the formed parts are estimated by using the X-ray diffraction technique on the inner and outer surfaces. It was found that the recorded residual stresses were changing from tensile to compressive ones along the formed part which is an indication of bending effects. Analytical evaluation of these effects reveals that the magnitude of the bending stress distribution is significant when compared to the material yield stress. Furthermore, the variation of sheet thickness was recorded in the same regions at which the XRD measurements were recorded. Experimental data show that there is a correlation between the residual and bending stress distributions with respect to the variation of the sheet thickness that affects the microstructural evolution of the aluminum parts. [ABSTRACT FROM AUTHOR]

This paper focuses on investigating the residual stress values associated with a part fabricated by Selective Laser Melting technology (SLM) when this is subjected further to forces on single point incremental forming (SPIF) operation of variable wall angle. The residual stresses induced by the SLM manufacturing process on the fabricated AlSi10Mg metallic sheets, as well as those produced during their forming SPIF operation were determined by X-ray diffraction (XRD) measurements. Significant residual stress levels of variation, positive or negative, along the metallic sample were observed because of the bending effects induced by the SPIF processes. It is also shown how the wall thickness varies along the additive manufactured SPIFed part as well as the morphology of the melting pools as a function of the deformation depth. [ABSTRACT FROM AUTHOR]

The exponential growth of additive manufacturing technologies is not only improving production processes to achieve functional requirements for products, but it could also help to minimize environmental impacts. In order to align a green product lifecycle management vision, companies need to implement emerging technologies and define a set of metrics that measure the benefits of the change. Each product requires a particular and optimized manufacturing process plan, and each production phase must achieve a significant reduction of critical metrics for the whole Life Cycle Assessment (LCA). This paper provides a comprehensive and comparative LCA of two manufacturing process plans for the case study of an aircraft engine turbine blade. The first process consists of a combination of Investment Casting and Precision Machining and the second consists in the replacement of Investment casting by Selective Laser Melting as an emergent process for near net shape fabrication. The collected data for the comparison includes Global Warming Potential (GWP), Acidification Potential (AP), Ozone layer Depletion Potential (ODP), Human Toxicity Potential (HTP), and Human Toxicity (HT) with cancer and non-cancer effects. The relative analysis shows that, for the critical indicators, an apparent improvement in CO 2 emissions reduction is achieved as well as in the other hazardous emissions. The results showed that the whole lifecycle of Conventional Manufacturing corresponds to 7.32 tons of CO 2 , while, the emission of the Additive Manufacturing is 7.02 tons of CO 2. The results analysis can be used for decision-making, and it can help for facing future comparative works to explore cleaner manufacturing technologies. • Process Modelling of Additive and Conventional Aerospace Manufacturing. • Data mining and simulation of manufacturing operations with a LCA tool. • Analysis of manufacturing process plan with Selective Laser Melting. • Sustainability Analysis of Investment Casting compared to Selective Laser Melting. [ABSTRACT FROM AUTHOR]