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| Author(s): |
Guilherme Origo Fulop
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Lorena. |
| Institution: | Universidade de São Paulo (USP). Escola de Engenharia de Lorena (EEL/ASDI) |
| Defense date: | 2022-04-28 |
| Examining board members: |
Cristina Bormio Nunes;
Thomas Gabriel Rosauro Clarke;
Renato de Figueiredo Jardim;
Maria José Ramos Sandim
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| Advisor: | Cristina Bormio Nunes |
| Abstract | |
Power transformers and electric motors are machines that end up by generating noise, due to the same reason, because these noises are originated from the magnetostriction of the material that composes the magnetic core of these machines. Magnetic cores are formed by thin sheets of ferromagnetic material, where the most commonly used material is grain oriented (GO) Fe-Si alloy in power transformers and non-oriented electrical steel (NO) in electric motors. In the present work, it was developed two alloys of Fe-Ti: Fe-4%Ti and Fe-7%Ti (% mass), produced by rolling and heat treatment sequences, particular to each sample. The 4% Ti alloy was cold rolled, while the 7% Ti alloy was hot rolled. The results obtained were compared to those of a commercial Fe-Si GNO alloy. The 4% Ti alloy has 22% higher relative magnetic permeability and lower magnetostriction than the Fe-Si alloy. Magnetostriction is negative in Fe-Ti alloys, while in Fe-Si it is positive. The two Fe-Ti alloys have the highest value of maximum magnetic induction consisting, respectively, of 1.83 T and 1.74 T for the Fe-Ti alloys with 4% and 7% Ti and 1.67 T for Fe-Si. However, the hysteretic loss of Fe-Ti alloys are much higher than those of commercial Fe-Si alloy GNO, due to the coercive field values (Hc) and remanent magnetic induction (Br) in Fe-Ti alloys being higher than in Fe-Si alloys. For the optimization of Fe-Ti alloys there are needed adjustments in the microstructural properties to be applied to the hysteretic losses. (AU) | |
| FAPESP's process: | 18/14939-0 - Production of Fe-Ti alloy sheets and improvement of their magnetic and microstructural properties for use in low-noise electric machines and transformers |
| Grantee: | Guilherme Origo Fulop |
| Support Opportunities: | Scholarships in Brazil - Doctorate |