Microstructure and physical properties of nanocrystalline Fe75B10Si10Cr5 alloy

The main of this paper is to study the microstructure and physical properties of the Fe75B10Si10Cr5 in condition after being produced. The sample was prepared as cylindrical rod with a diameter of 3 mm. The rod was produced using the arc melting method with a suction casting option. It was found that produced alloy was nanocrystalline with average grains of about 15 nm. Due to the different cooling rates in the inner and outer part of the rod, variable sizes of dendrites in the material were observed. The presence of the dendrites was also confirmed on the surface by AFM investigations. The average roughness calculated for chosen profile of the examined area was 6 nm and average hardness of the material equals 844 HV. The mechanical properties were determined in respect to the Oliver-Pharr method. Young’s modulus of the Fe75B10Si10Cr5 calculated from load-displacement curve equals 128 GPa. Magnetic properties of the sample were measured by the vibrating sample magnetometer. The coercivity was equaled 2.184 kA/m, which is relatively low. It means that the Fe75B10Si10Cr5 alloy is magnetically soft.