熔融Ni-(Cr, Co, W)合金的表面张力及偏聚现象

采用改良静滴法测定了熔融Ni-（Cr，Co，W）二元舍金在Ar＋3%H2气氛下1773-1873K温度范围内的表面张力数据，采用Butler方程计算并分析了（Cr、Co、W等组元在合金中的偏聚现象。结果表明，表面张力的计算值和实测值具有良好的一致性，合金的表面张力随着温度的升高而下降。自由电子数目较少，表面张力较小的组元在表面偏聚，溶质元素的原子半径与溶剂元素相比相差越大，舍金熔体的偏聚现象越严重，最终导致Ni在表面富集，而Co、W在合金内部偏聚。     

Surface tension of molten Ni-（Cr, Co, W） alloys and segregation of elements

Surface tension of molten Ni-(Cr, Co, W) alloys was measured at the temperature of 1 773-1 873 K in an Ar+3%H2 atmosphere using an improved sessile drop method. The segregation of Cr, Co and W in alloy was calculated and analyzed using Butler's equation. The results show a good agreement between measured and calculated data. The surface tension of molten Ni-(Cr,Co, W) alloys decreases with increasing temperature. In Ni-(Cr, Co, W) alloys, the element with lower surface tension tends to segregate on the surface of molten alloy while that with higher surface tension tends to segregate inside of the molten alloy. The larger the differences in surface tension, atom radius and electron configuration between solvent and solute are, the more significant the segregation is. As a result, Ni segregates onto the surface and Co and W segregate inside the alloys.     

用改良静滴法测量液态Ni基合金的密度和摩尔体积

采用改良静滴法测量并通过软件的计算得到了4种商用镍基合金的密度.结果表明,随着温度的升高,4种液态镍基合金的密度逐渐减小,摩尔体积逐渐增大.与理想混合状态相比,液体镍基合金的摩尔体积出现负偏差.从而可以推测在合金中各种原子之间发生了调整.     

熔融Ni-W合金的表面张力研究

采用改进静滴法测定了1773～1873 K温度范围内熔融Ni-(5～10)W(质量分数,%)合金在Al2O3基板上于Ar 3%H2气氛下的表面张力数据.熔融Ni-W合金的表面张力随着温度的升高而降低.在此基础上采用Butler模型推导了表面张力随温度与浓度的变化情况,计算了合金体系中元素的偏聚情况.表面张力的计算结果与测量值的符合度较高.W在合金表面的浓度低于体相浓度.     

Densities of molten Ni-（Cr,Co, W） superalloys

In order to obtain more accurate density for molten Ni-（Cr, Co, W） binary alloy, the densities of molten pure Ni and Ni-Cr, Ni-Co, Ni-W alloys were measured with a sessile drop method. It is found that the measured densities of molten pure Ni and Ni-Cr, Ni-Co, Ni-W alloys decrease with increasing temperature in the experimental temperature range. The density of alloys increases with increasing W and Co concentrations while it decreases with increasing Cr concentration in the alloy at 1 773-1 873 K. The molar volume of Ni-based alloys increases with increasing W concentration while it decreases with increasing Co concentration. The effect of Cr concentration on the molar volume of the alloy is little in the studied concentration range. The accommodation among atomic species was analyzed. The deviation of molar volume from ideal mixing shows an ideal mixing of Ni-（Cr, Co, W） binary alloys.     

液态树脂基材料与铜基材料的界面润湿现象分析

采用静滴法观察了液态树脂基材料与铜基材料的界面润湿现象,测定了298～363 K温度范围内的接触角,计算了附着功.结果表明:接触角随时间呈下降趋势,基板表面粗糙度对接触角的影响较大,在表面粗糙度较小时,接触角随时间下降较快,平衡接触角较小;初始接触角和平衡接触角均随树脂基材料中环氧树脂含量的增加而降低;升高温度使接触角的变化速率加快,加入树脂后的液体的平衡接触角对温度更加敏感;附着功随着时间的延长逐渐增加,但随着温度的上升而减小.