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在工业性设备上测定不同熔炼条件下电渣重熔过程中渣池内温度分布情况的结果表明,渣池内径向和轴向温度分布不均匀。径向由电极中心至结晶器壁,轴向由金属熔池/渣池界面至渣/气界面,温度逐渐降低。在靠近渣/气界面处,轴向温度变化剧烈。在一定的试验条件下,在电极圆柱表面至结晶器壁的1/2距离处,轴向温度分布可用下式表示: t=1675exp(-1.074/l),(5毫米≤l≤210毫米) 其中:t=渣温,℃;l=距渣/气界面距离,毫米。 轴向温度差大于300℃,渣面温度低于1350℃。 同时发现:渣池内存在着一个“高温区间”,其中温度分布较均匀,温差约为30℃;当结晶器对底水箱不绝缘或电流可以从结晶器壁流向钢锭时,由于渣/气界面温度升高,影响到氧的输入和化学反应物和生成物传递的加速,从而使高温合金中钛烧损值增加。

Temperature distribution round the molten slag pool in the process of electro-slag refining has been studied under various industrial conditions. It was found thatthe temperature of the molten slag pool along the radial direction and thatalong the axial direction were uneven. A decreasing temperature gradient was observ-ed along radial direction from eletrode centre to mould wall and along axial directionfrom molten metal pool/slag interface to slag/atmosphere interface. At the slag/atmo-sphere interface the temperature dropped sharply. Under certain experimental condi-tions the change of temperature along the axial direction at the middle of the distancebetween the electrode cylindrical surface and mould wall was found in accordancewith: t=1675 exp(-1.074/l),(5mm≤l≤210mm)where t = the slag temperature, ℃; l=the distance from the slag/atmosphere in-terface, mm. The difference between axial temperatures was greater than 300℃,and the temperature at slag/atmosphere interface was below 1350℃. In the molten slag pool, there existed a "high temperature region" in whichthe temperature distribution appeared to be rather even and its temperature gra-dient was only about 30℃. If the insulation of the mould from its base platewas poor, thus allowing electric current flowing from the mould wall to ingot, thetitanium loss during the electroslag refining of superalloys would be great, becausethe rather high temperature at the slag/atmosphere interface rendered the admis-sion of a greater amount of oxygen as well as promoted a more rapid transferof chemical reactants and products.