Influence of Nb addition on the magnetic and mechanical properties of Fe-35%Co alloy (mass %)

• Grant number: 22/09152-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2022
• End date: November 30, 2023
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Cristina Bormio Nunes
• Grantee: Matheus Marinho Arruda
• Host Institution: Escola de Engenharia de Lorena (EEL). Universidade de São Paulo (USP). Lorena , SP, Brazil
• Associated scholarship(s): 22/15334-0 - Survey of piezomagnetic properties of Fe-35%Co alloys (% by mass) with addition of 0.5 and 0.7% of Nb, BE.EP.IC

Abstract

Fe-Co alloys with lower amounts of Co (27 < %Co < 35) compared to commercial equiatomic alloys (48Fe:48Co:2V) are relevant to be studied, as they have high saturation magnetizations, high Curie temperatures and are cheaper, as they contain less cobalt. Considering only raw material prices, a ton of Fe-Co equiatomic alloy costs about 11200 USD more than alloys with 35% Co. Currently, the price of Co per ton is 75000 USD, and for the iron contained in iron ore is 260 USD. In the literature there is practically no data on these alloys of lower Co concentrations. For the alloy with 35% Co, the only work that deals with these properties is from 1947. It is worth mentioning that it is a patented product. Therefore, we understand that it is important that Fe-Co alloys with a lower value of Co than the equiatomic alloy are revisited and studied more in depth and in a systematic way, making the correlation of materials science/engineering with the physical properties of the material. In addition, the purity of the materials may have some influence on the new results, as the available results are already 75 years old. This understanding may help in the future in some alloy formulation that will improve the magnetic and mechanical performance of these materials so that they can be used in electrical machines that will lead to greater energy efficiency. In particular, the demand for energy efficiency applies to electric cars and aircraft. For the present project, the object of study is the Fe-Co alloy with 35% by mass of Co with the addition of Nb. The addition of Nb aims to improve the ductility of the alloy and the effects of this addition on the magnetic properties of the material will be analyzed. Another reasons for this choice is that the alloy with 35% Co, compared to the alloy with 30% Co that we have already studied in a previous project, with only an increase of 5% Co, may have an increase in permeability, since the alloy with 35% has a lower value of K1, the first anisotropic constant, which will cause the anisotropic field to decrease.(AU)