Optimization of the process parameters for the manufacturing of open-cells iron foams with high energy absorption

Girolamo Costanza, Gjergj Dodbiba, Maria Elisa Tata
2016 Procedia Structural Integrity  
During their operation, modern aircraft engine components are subjected to increasingly demanding operating conditions, especially the high pressure turbine (HPT) blades. Such conditions cause these parts to undergo different types of time-dependent degradation, one of which is creep. A model using the finite element method (FEM) was developed, in order to be able to predict the creep behaviour of HPT blades. Flight data records (FDR) for a specific aircraft, provided by a commercial aviation
more » ... mmercial aviation company, were used to obtain thermal and mechanical data for three different flight cycles. In order to create the 3D model needed for the FEM analysis, a HPT blade scrap was scanned, and its chemical composition and material properties were obtained. The data that was gathered was fed into the FEM model and different simulations were run, first with a simplified 3D rectangular block shape, in order to better establish the model, and then with the real 3D mesh obtained from the blade scrap. The overall expected behaviour in terms of displacement was observed, in particular at the trailing edge of the blade. Therefore such a model can be useful in the goal of predicting turbine blade life, given a set of FDR data. Abstract In this work the main results of the experimental research aimed to manufacture iron foams are reported. Iron powders (base metal) have been mixed with urea (filler agent) in different relative amounts (60% Fe-40% urea, 50-50, 40-60 and 30-70) and then compressed in a cylindrical die in order to obtain a compact precursor. After compaction, the filler agent has been removed from each precursor in boiling water. The successive manufacturing step has been sintering and for this operation the optimum temperature has been found at 950 °C. Finally such foams have been subjected to compressive tests. Different amounts of Fe and urea match with different density and mechanical behavior in compressive tests. Energy absorbed during deformation has been calculated from the stress-strain compressive curve. Plateau stress, total strain and absorbed energy during deformation have been found strictly dependent from the iron/urea ratios. Abstract In this work the main results of the experimental research aimed to manufacture iron foams are reported. Iron powders (base metal) have been mixed with urea (filler agent) in different relative amounts and then compressed in a cylindrical die in order to obtain a compact precursor. After compaction, the filler agent has been removed from each precursor in boiling water. The successive manufacturing step has been sintering and for this operation the optimum temperature has been found at 950 °C. Finally such foams have been subjected to compressive tests. Different amounts of Fe and urea match with different density and mechanical behavior in compressive tests. Energy absorbed during deformation has been calculated from the stress-strain compressive curve. Plateau stress, total strain and absorbed energy during deformation have been found strictly dependent from the iron/urea ratios.
doi:10.1016/j.prostr.2016.06.285 fatcat:e6oodn3zzva3nnotgnbwripmdy