| Autor: |
Scherman E; Mechanical Engineering, LUT School of Energy Systems, LUT University, P.O. Box 20, 53851 Lappeenranta, Finland.; Department of Technology, LAB University of Applied Sciences, Yliopistonkatu 36, 53850 Lappeenranta, Finland., Sikanen E; Mechanical Engineering, LUT School of Energy Systems, LUT University, P.O. Box 20, 53851 Lappeenranta, Finland., Yeddu HK; Mechanical Engineering, LUT School of Energy Systems, LUT University, P.O. Box 20, 53851 Lappeenranta, Finland., Amraei M; Mechanical Engineering, LUT School of Energy Systems, LUT University, P.O. Box 20, 53851 Lappeenranta, Finland.; Department of Mechanical and Materials Engineering, University of Turku, 20520 Turku, Finland., Sopanen J; Mechanical Engineering, LUT School of Energy Systems, LUT University, P.O. Box 20, 53851 Lappeenranta, Finland. |
| Abstrakt: |
High-speed electric motors, e.g., axially laminated anisotropic synchronous reluctance motors (ALA-SynRM), use a solid rotor manufactured by joining alternating layers of magnetic and non-magnetic metallic sheets. The strength of the dissimilar metallic joints is critical for the rotor's ability to withstand the operating conditions of the high-speed electrical machine. In this work, various dissimilar metallic joint configurations that can be used in high-speed ALA-SynRM rotors are studied by analyzing the shear strength, microstructure, hardness, and composition of the joints. Metallic joints of structural steels and Inconel ® alloys fabricated by vacuum brazing and hot isostatic pressing (HIP) are studied. Finite element analysis (FEA) was performed to calculate the maximum shear stress of the joints that were subjected to various high speed operating conditions. The shear strength of the test specimens was measured and compared with FEA results. The microstructure and chemical composition of the joints were studied by using optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) on SEM. The results show that the hot isostatic pressed S1100MC-IN718 joint achieved the highest ultimate shear strength (233.3 MPa) followed by vacuum brazed S355MC-IN600 joint (230.1 MPa) and HIP S355-IN718 (203.5 MPa), thereby showing that vacuum brazing and HIP can be viable manufacturing methods to fabricate a high-speed ALA-SynRM rotor. |
