The Preparation Of 1J79 Soft Magnetic Alloy

1J79 soft magnetic alloy was prepared by the vacuum electric arc smelting.lt is investigated that the heat treatment specification acts on the magnetic properties for 1J79 soft magnetic alloy.In addition,the effect for a amount of Ni,Mo on the magnetic properties is dealt with in 1J79 soft magnetic alloy.EPMA was used to observe its crystal growth and the content of impurity.Magnetic properties and hysteresis loops were investigated by Vibrating Sample Magnetometer(VSM).The results are as follows:firstly,a two-stage un-intermittent heat treatment specification is of great benefit to ridding impurity,at the same time, the coercivity of un-intermittent heat treatment samples was decreased obviously and saturation magnetization was increased slightly.Secondly, it is also investigated that different annealing time acts on the magnetic properties of 1J79 alloy under two-stage un-intermittent heat treatment specification. Experimental results show that prolonging annealing time makes for crystal growth,at the same time, it decreases intracrystalline flaw and makes domain wall movement easy, hence magnetic properties increase. But if the annealing time is too long, the magnetic properties will reduce possibly.Because in high temperature,the longer annealing time is,the worse furnace atmosphere is,which results in worsening of magnetic properties.Therefore,when the annealing time is prolonged to 4 hour, on the one hand, it can improve the heat treatment efficiency;on the other hand, magnetic properties of 1J79 alloy increase too. All kinds of factors indicate that it is optimal that a two-stage un-intermittent heat treatment specification with 950 ℃ ×4hr+1100℃ ×4hr and furnace cooling.Finally, it is investigated that the alloy containing 78wt%, 79wt%, 80wt% of Ni and the small amount of Mo additive acts on the magnetic properties for 1J79 soft magnetic alloy. It is found that a small change of Ni dose not affect the magnetic properties obviously. On the other hand, the small amount of Mo additive is useful to improve the saturation magnetization and reduce coercivity.The 1J79 alloy containing 78.00wt% of Ni, 5.00wt % of Mo, 0.90 wt % of Mn and 0.40wt % of Si is determined via the above research work.The said alloy possesses the best overall properties.