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Advanced remanufacturing by additive manufacturing is challenging in aerospace due to the minimization of material costs, preparation times and metal waste. This study analyzed a 40HM low-alloy steel ring as a demo tooling used to produce aircraft engine components. The possibility of using laser cladding with powder process with the additive material NiCrBSi alloy powder was analyzed. Optimal parameters of the process were selected in terms of the assumed structural requirements (geometrical parameters of the clad, its hardness and the size of the heat-affected zone) for the remanufactured surfaces, ultimately obtaining a crack-free multilayer coating with a thickness of 2 mm and a hardness of above 700 HV1. The remanufacturing process was performed on three representative surfaces: flat face, cylindrical external, and internal. This approach allowed an analysis of the possibilities of finishing the laser-deposited layers with the machining methods used in the actual tooling department of the aerospace company: turning, milling, grinding, and center grinding. During chip processing, the defects (holes, cracks) made machining difficult and ineffective, mainly due to accelerated tool wear. Single cracks were observed after the grinding operation, which may reduce the durability of the remanufacturing layer. Both the changes in the microstructure of the demo component and the phases present in the cladding were analyzed. The deposition process was found to form a martensitic structure in the substrate at the cross-section in proximity to the remanufactured surfaces. This was also confirmed by an increase in average hardness from 402 HV1 to 605 HV1 for the analyzed substrate areas.

In this study, binary Al-2.3wt%Li alloy, ternary Al-2.2wt%Li-0.1wt%Zr alloy and quaternary Al-2.2wt%Li-0.1wt%Zr-1.2wt%Cu alloy in the solution treated condition and additionally in aging condition were severely plastically deformed by rolling with cyclic movement of rolls (RCMR) method to produce ultrafine grained structure. Scanning transmission electron microscopy (STEM), scanning electron microscopy with EBSD detector (SEM/EBSD) were used for microstructural characterization and hardness test for a preliminary assessment of mechanical properties. The results shows, that the combination of aging treatments with RCMR deformation can effectively increase the hardness of Al-Li alloys. Second particles hinders the annihilation of dislocations in Al matrix during deformation leading to an increase of dislocation density. Significant amount of nanometric second particles in refined structure to ultrafine scale especially in Al-2.2wt%Li-0.1wt%Zr-1.2wt%Cu alloy effectively prevents the formation of high angle boundaries.

In this study, binary Al–2.3wt%Li alloy, ternary Al–2.2wt%Li–0.1wt%Zr alloy and quaternary Al–2.2wt%Li–0.1wt%Zr–1.2wt%Cu alloy in the solution treated condition and additionally in aging condition were severely plastically deformed by rolling with cyclic movement of rolls (RCMR) method to produce ultrafine grained structure. Scanning transmission electron microscopy (STEM), scanning electron microscopy with EBSD detector (SEM/EBSD) were used for microstructural characterization and hardness test for a preliminary assessment of mechanical properties. The results shows, that the combination of aging treatments with RCMR deformation can effectively increase the hardness of Al–Li alloys. Second particles hinders the annihilation of dislocations in Al matrix during deformation leading to an increase of dislocation density. Significant amount of nanometric second particles in refined structure to ultrafine scale especially in Al–2.2wt%Li–0.1wt%Zr–1.2wt%Cu alloy effectively prevents the formation of high angle boundaries.

Experiments were conducted to investigate the development of an ultrafme grain structure during compression with oscillatory torsion processing of high-purity aluminum (99.9%) with an initial grain size of 75 μm. The samples were processed using different deformation parameters: torsion frequency (f) and compression rate (υ). The samples were examined using a scanning electron microscope equipped with a field emission gun and an electron backscattered diffraction detector. The results suggest that for high-purity aluminum an ultrafine-grained microstructure was obtained after a total effective strain (εft) of 45 in samples deformed at f= 1.6 Hz and υ= 0.04 mm/s. A quantitative study of the microstruc-tural parameters showed that the area fraction of the ultrafine grains (<1 μm) (A1μm) was 44%, the fraction of high-angle boundaries was 53%, and the average diameter of the grains was about 600 nm. The yield stress and ultimate tensile stress reached 127 and 137 MPa, respectively, after deformation at a total effective strain of 45. When the total effective strain reached 120, the mechanical strength of the material decreased. This suggests that the decrease in strength is associated with the operation of the recovery mechanism that decreases the boundary volume.

Experiments were conducted to investigate the development of an ultrafine grain structure during compression with oscillatory torsion processing of high-purity aluminum (99.9%) with an initial grain size of 75μm. The samples were processed using different deformation parameters: torsion frequency (f) and compression rate (v). The samples were examined using a scanning electron microscope equipped with a field emission gun and an electron backscattered diffraction detector. The results suggest that for high-purity aluminum an ultrafine-grained microstructure was obtained after a total effective strain (ɛft) of 45 in samples deformed at f=1.6Hz and v=0.04mm/s. A quantitative study of the microstructural parameters showed that the area fraction of the ultrafine grains (<1μm) (A1μm) was 44%, the fraction of high-angle boundaries was 53%, and the average diameter of the grains was about 600nm. The yield stress and ultimate tensile stress reached 127 and 137MPa, respectively, after deformation at a total effective strain of 45. When the total effective strain reached 120, the mechanical strength of the material decreased. This suggests that the decrease in strength is associated with the operation of the recovery mechanism that decreases the boundary volume.

The influence of compression with oscillatory torsion on the copper structure and force parameters are presented. The compression with oscillatory torsion method, developed in the Faculty of Materials Science and Metallurgy at the Silesian University of Technology, is used to achieve severe plastic deformation resulting in homogeneous ultrafine-grained structure of metals.

The influence of compression with oscillatory torsion on the copper structure and force parameters are presented. The compression with oscillatory torsion method, developed in the Faculty of Materials Science and Metallurgy at the Silesian University of Technology, is used to achieve severe plastic deformation resulting in homogeneous ultrafine-grained structure of metals.