Effect of oxygen on the surface tension of liquid copper

The influence of oxygen on the surface tension of liquid copper has been determined by the sessile drop technique. The surface tension of pure liquid copper at 1108 °C is found to be equal to 1.320 ± 0.015 N/m. The effect of oxygen is investigated for partial pressures of oxygen ranging from 10?13 to 5 X 10?6 atm. The surface activity of oxygen is deduced to equal 3200 ± 600 N/m and the saturation adsorption to equal 5.72 X 10"6 mole/m², which corresponds to a saturation area of 29 ±5Ų per adsorbed oxygen atom. The adsorption of oxygen on liquid copper is consistent with the formation at the metal surface of a two-dimensional compound of stoichiometry Cu³O. It is also concluded that equivalent attractive forces operate between neighboring adsorbed atoms.     

Effect of the electric potential on the surface tension of iron

The effect of the electric potential on the surface tension of silicon iron is studied. The effects of the electric potential on the microhardness and the surface tension coefficient of silicon iron are found to have the same character. A linear relation between the electric potential and the surface tension is detected at φ ≤ 1 V.     

Effect of carbon and sulphur on the surface tension of molten iron

Surface tensions of Fe‐4%C‐S alloys were measured at 1623 and 1823 K using the sessile drop technique. Thermodynamic models based on Butler's equation for surface tension of liquid alloys have been compared with experimental results. Calculated values are found to be in good agreement with those of the experimental data of the system. At the same sulphur activity, the effect of carbon on the surface tension of Fe‐C‐S alloys was found to extrude only when the sulphur content was less than 0.005 %.     

Effect of carbon on the surface properties of liquid iron

Conclusions A study was made of the effects of temperature and composition on of Fe-C melts. It was found that, in the hypoeutectic range of compositions, the polytherms of of the melts investigated are not straight lines and are characterized by a positive temperature coefficient of . Carbon exhibits surface activity in liquid iron. A hypothesis is advanced in explanation of this phenomenon. The wetting of alumina by Fe-C melts was investigated at various carbon concentrations and temperatures. Raising the carbon content improves wetting in the system (Fe-C)_L-A1₂O₃.Translated from Poroshkovaya Metallurgiya, No. 10 (118), pp. 57–61, October, 1972.     

Effect of arsenic on the activity of oxygen dissolved in dilute liquid copper solutions

The influence of arsenic additions on the activity of oxygen in liquid copper was studied by the solid-electrolyte galvanic cell (−) Pt, W/Cu-O-As ∥ ZrO₂-CaO ∥ NiO-Ni/Pt (+) in the temperature range 1373 to 1473 K. The activity coefficient of oxygen in liquid copper was found to be unaffected by the addition of arsenic. The interaction parameter values for group V B elements in the periodic table with respect to oxygen are discussed in the light of the solute interactions in copper. H. Walqui, Formerly on leave at the Department of Theoretical Metallurgy, The Royal Institute of Technology     

Influence of phosphorus addition on the surface tension of liquid iron and segregation of phosphorus on the surface of Fe-P alloy

This article presents a study of the surface tension and phosphorus surface segregation in Fe-P alloys. The surface tension was measured by the sessile drop technique. The result of the dynamic surface tension for the low phosphorus content alloys shows that the alloy surface vaporization has a clear effect on the surface tension and causes a positive surface tension temperature coefficient. However, from this article, it is evident that phosphorus in liquid iron acts as a surface active element similar to arsenic. The surface segregation was determined using Auger electron spectroscopy. The result on the surface analysis of as-solidified sample indicates that the adsorption of impurity elements, such as oxygen, carbon, and nitrogen, can conceal phosphorus segregation on the free surface. Phosphorus segregation was also examined in the samples as-cleaned by Ar⁺ and then treated 30 minutes at 650°C. Phosphorus was found to segregate extensively on the surface of the alloys. On the basis of the analysis of the published data, the surface active intensity sequence of some nonmetallic elements was arrayed, and the surface active intensity of fluorine and boron in liquid iron was estimated.     

Effect of temperature on the structure of liquid iron

Review of published data on the properties of liquid iron at different temperatures. Conclusion supporting a proposal that a structural change takes place in the melt.     

Effect of slag inclusions on the density and the surface tension of liquid 32G2 and 32G1 steels

The density and the surface tension of liquid 32G2 and 32G1 steels are experimentally studied. Samples are cut from oil-and-gas pipes having different degrees of imperfection. The experimental results are used to find the effect of the defects detected by magnetic-powder and ultrasonic inspection methods on the temperature dependences of the density and the surface tension of liquid 32G2 and 32G1 steels. The results obtained are interpreted in terms of the concepts of a microheterogeneous structure of metallic melts. Microheterogeneities are irreversibly destroyed when the liquid 32G2 steel is heated to 1700°C and the 32G1 steel, to 1750°C.     

各向异性表面张力对柱晶界面形态的影响

本文研究了拟稳态时各向异性表面张力作用下柱晶界面的生长行为.在运用渐近分析方法求解柱晶界面形态数学表达式的基础上,分析在不同各向异性表面张力强度影响下柱晶界面形态的变化.各向异性表面张力对柱晶界面形态有显著影响.在柱晶生长开始阶段,柱晶部分界面首先向内收缩,当收缩达到某个临界值后,界面开始向外生长.柱晶界面沿着优先生长方向更快地生长.柱晶界面形态上形成突起变形,各向异性表面张力强度越大,柱晶界面形态的突起变形越明显.     

氧分压对铁矿粉烧结成矿的影响

氧分压一直是影响烧结矿质量的重要因素.通过控制不同氧分压进行的烧结实验结果表明:在氧化性气氛下,生成的矿物主要有赤铁矿和铁酸钙,出现了针状铁酸钙晶形.氧分压从7.10×10^-4至7.89×10^-5Pa时,矿物组成区别不大,只是在局部产生少量的磁铁矿.氧分压从4.44×10^-5Pa开始,赤铁矿明显减少而磁铁矿增加.在高碱度烧结矿中,为了获得合理的烧结矿矿物组成与形态结构,氧分压应控制在2.12×10⁴~7.10×10^-4Pa之间.     

Effect of enriching the blast with oxygen on the production cost of pig iron

Conclusion By mathematically modeling the blast-furnace smelting of conversion pig iron with a change in the oxygen content of the blast from 21 to 30% and a change in blast temperature from 800 to 1400°C, it was possible to determine how blast temperature affects the increases that occur in furnace productivity, coke rate, and pig-iron cost when blast oxygen content is increased by 1% within the ranges from 21 to 25% and from 25 to 30%. Under the furnace operating conditions that were examined, the savings in coke realized when the blast is enriched with oxygen decrease as blast temperature increases. In fact, coke rate increases at blast temperatures above 1100°C when the blast is enriched with oxygen in the range 25–30%. The effect of oxygen enrichment on pig-iron cost within this concentration range is negative throughout the range of blast temperatures examined. Adding more oxygen to the blast reduces the production cost of the pig iron only when blast oxygen content is within the range 21–25% and blast temperature is no greater than 1000–1100°C. At higher temperatures, adding more oxygen to the blast is economically inexpedient even within the lower ranges of oxygen content. Moscow State Institute of Steel and Alloys. Translated from Metallurg, No. 5, pp. 43–44, May, 1999.     

铁粉和石墨粒径对Fe-C系预混合粉性能的影响

以不同粒度分布的还原铁粉及石墨为原料,采用粘结剂处理工艺制备Fe-C系预混合粉。研究了铁粉粒度分布、石墨粒径对预混合粉石墨粘结效率、松装密度、流动性以及烧结件密度、抗弯强度、硬度等性能的影响。结果表明,粒度分布均匀的铁粉有利于提高预混合粉的松装密度、流动性和压坯性能,石墨粒度为-2 000目的预混合粉中,石墨分布更加均匀,石墨的粘结效率为98.3%,其工艺性能和烧结性能更好。     

The effect of zirconium,cerium, and lanthanum on the solubility of oxygen in liquid iron

The effect of zirconium, cerium, and lanthanum up to about 1 wt pet on the solubility of oxygen in liquid iron in equilibrium with an oxide phase at 1680°C was measured. All three elements are strong deoxidizers of iron, and the oxygen solubility minimums were 10 ppm or less at 0.05 to 0.1 wt pet of the alloying element. The interaction coefficients were estimated from the results giving e_o ^zr = −3, e_o ^Ce = −3, and e_o ^La = −5. When the concentration of the alloying element is expressed in wt pet, the effect of each of the three elements (Zr, Ce, and La) on the activity and solubility of oxygen in liquid iron is similar to that of aluminum.     

Effect of dendrite coarsening on the solidification of interdendritic liquid in iron alloys

The solidification of the interdendritic liquid in austenitic 110G13L steel and white cast iron is studied. In the absence of dendrite coarsening, the solidification mechanism of the interdendritic liquid in the manganese steel is shown to change and solidification occurs in the form of polycrystalline aggregates around dendrites from different centers. The relation between the standard solidification of the interdendritic liquid and the dendrite coarsening in iron alloys is grounded.     

溶解氧对X80管线钢腐蚀行为的影响及其机制

通过交流阻抗技术、动电位极化技术以及X射线衍射仪,研究了溶解氧含量对X80管线钢在库尔勒土壤模拟溶液中电化学行为的影响。结果表明:随着溶解氧含量的不断降低,腐蚀电流密度明显减小,金属腐蚀速率显著下降。这是因为溶解氧含量的不同会导致试样腐蚀产物差异,从而造成了试样在库尔勒土壤模拟溶液中腐蚀速率的变化。当溶解氧含量降到0.35mg/L时,金属电极表面生成了一层以FeCO3为主的腐蚀产物膜,FeCO3明显抑制了腐蚀反应的进行,产物膜对X80钢起到保护作用,此时试样腐蚀现象最不明显。     

Effect of titanium dioxide on the surface tension and density of an aluminocalcium oxide-fluoride melt

The effect of titanium oxides on the surface tension and density of an Al₂O₃-CaO-CaF₂ melt is studied. At 1773–1923 K, an addition of 4–25 mol % TiO₂ to an oxide-fluoride melt decreases the surface tension and increases the density. The complexation properties of titanium in the oxide-fluoride slags are revealed, and the size and character of the structural units are determined.     

添加剂对铝酸钠溶液晶种分解附聚过程的影响

研究了工业结晶助剂(Nalco)、脂肪醇、脂肪酸及醚类添加剂对铝酸钠溶液晶种分解附聚过程的影响,并探讨了其作用机理。结果表明:添加工业结晶助剂(Nalco)有助于降低种分过程细粒子数,提高分解率;添加脂肪醇也能改善产品粒度分布;添加脂肪酸可以提高种分分解率;将脂肪醇乳化后能使产品细粒子数进一步减少,分解率也得到提高。