Effect of Secondary Decomposition on Coercivity of Fe-Co-Cr Alloys with 15% Co

Abstract:

The microstructure and magnetic properties of Fe-Co-Cr alloys with 15 wt % Co were investigated using transmission electron microscopy and magnetic measurements. The secondary decomposition within both the α₂-phase matrix and the α₁-phase particles was observed for magnets subjected thermo-magnetic treatment and subsequent stepped aging or continuous-cooling treatments. During high-temperature treatments (630-600 ^оC), when the α₂ phase is dominant (the volume fraction is more than 50%), the secondary decomposition of this phase takes place (α₂ → α_1' + α_2'). The deterioration of magnetic insulation of α₁-phase particles results in the decrease in the coercive force of alloys. Below 600 ^оC, when the α₁ phase is dominant (the volume fraction is more than 50%), the splitting of elongated α₁-phase particles occurs. When the temperature of stepped-aging decreases in high steps, the secondary decomposition (α₁ → α_1' + α_2') leads to the splitting of initial α₁-phase particles into fine slightly elongated particles and the decrease in the coercive force.

• Periodical: Solid State Phenomena (Volumes 233-234)
• Pages: 623-628
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.233-234.623
• Online since: July 2015
• Authors: Vladimir P. Menushenkov*, Vladimir S. Shubakov
• Keywords: Continuous Cooling, Fe-Co-Cr Alloys, Magnetic Properties, Secondary Decomposition, Stepped Aging

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