RH-KTB预熔渣深脱硫实践

在宝钢炼钢厂300 t RH-KTB上进行了超低碳超低硫钢的预熔渣深脱硫试验。试验共12炉,预熔渣加入量为4 kg/t。试验结果表明,在RH平均初始w(S)为42.1×10-6条件下,处理终点平均w(S)达到30×10-6,最低w(S)达到22×10-6,最高脱硫率达到36.6%,平均脱硫率达到28.6%,取得了较好的深脱硫效果。采用预熔渣处理过程钢中w(TO)及w(N)均有所降低。试验炉次钢中最低w(TO)为12×10-6,平均w(TO)为13.3×10-6,最低w(N)为11×10-6,平均w(N)为13.8×10-6。RH终点钢中的夹杂物主要是Al2O3,95.1%的夹杂物小于5μm。     

炼油热壁加氢反应器用超纯净焊材用钢

因反应器在 32 0～ 5 5 0℃ ,14～ 2 2MPa和加氢条件下使用 ,炼油厂热壁加氢反应器筒体焊缝材料3Cr 1Mo 0 .2 5V ,2 .2 5Cr 1Mo V ,9Cr 1Mo等钢均要求高的纯净度 :P≤ 0 .0 0 3% ,S≤ 0 .0 0 3% ,H≤ 2× 10 - 6 ,O≤ 30×10 - 6 ,N≤ 80× 10 - 6 ,回火脆化敏感系数J =(Si+Mn) (P +Sn)× 10 4 ≤ 10 0 % ,X =(10P +5Sb +4Sn +As)× 10 - 2 ≤15× 10 - 6 。讨论了超纯净度焊材用钢生产工艺和研发的可行性。     

IF钢试生产实践

为提高鞍钢三炼钢生产的IF钢质量,对三炼钢转炉-RH精炼-连铸生产IF钢的工艺过程开展了较为系统的分析研究。研究发现试生产中RH真空精炼过程[C]含量过高,浇铸过程中增碳、二次氧化比较严重,经改进调整之后,铸坯中w(C)在30×10-6左右,w(N)在25×10-6以下,w(T.O)在20×10-6左右,达到了较高的洁净度水平。     

衡钢管线用洁净钢EBT EAF-LF(VD)-HCC工艺生产实践

衡阳钢管公司用 30tEBT电弧炉、LF(VD)和水平连铸工艺生产的管线钢洁净度为 :P≤ 0 .0 15 % ,S≤ 0 .0 0 6 % ,H 2× 10 - 6 ,N≤ 5 0× 10 - 6 ,O(15～ 30 )× 10 - 6 ,As+Sn +Pb +Sb +Bi≤ 0 .0 5 0 %。     

60Si2MnA弹簧钢脱氧工艺的优化

在现场调研的基础上 ,对用 30 t L F生产 6 0 Si2 Mn A弹簧钢的脱氧工艺进行优化控制。结果表明 :在不进行夹杂物变性处理的条件下 ,可生产出平均氧含量为 2 3× 10 - 4 %、最低氧含量为 16× 10 - 4 %的 6 0 Si2 Mn A弹簧钢     

提高高碳钢洁净度的冶炼工艺研究

在电弧炉-LF-小方坯连铸工艺生产高碳钢时,通过配加直接还原铁和铁水及生铁、改进电炉出钢脱氧脱硫方法、采用合理的精炼渣系和精炼后的吹Ar软搅拌,加强保护浇铸等措施,显著提高了钢的洁净度。使得成品的总w(O)达到15×10-6左右、w(N)在45×10-6左右、w(P)≤12×10-5、w(S)在5×10-5左右。钢中当量直径(5μm)的氧化物显微夹杂数量平均达到3.29个/mm2、84%的氧化物夹杂尺寸小于5μm,并且小方坯中大型夹杂物总量为5.48mg/10kg。     

60Si2CrVAT弹簧钢EAF-LF(VD)-CC工艺实践

用 10 0tUHPEAF +LF(VD) + 30 0mm方CC工艺生产提速铁路车辆用弹簧钢 6 0Si2CrVAT的工艺实践表明 ,钢的清洁度为 [O]10× 10 - 6 ,S 0 .0 0 5 % ,P 0 .0 12 % ,连铸时用结晶器 +凝固末端电磁搅拌 ,使连铸坯中心碳偏析指数达 1.0 8。     

高压气瓶用钢34Mn2V连铸坯的生产实践

包钢采用 80t转炉 ,83tLF(VD) ,4流弧形连铸机生产断面为 (mm) :2 80× 32 5、2 80× 380、319×4 10高压气瓶用钢 34Mn2V连铸坯 ,LF(VD)后的平均成分为 (% ) :0 34C ,0 2 5Si,1 5 9Mn ,0 0 15P ,0 0 0 4S ,0 10V ,LF(VD)脱硫率为 84 6 2 % ,钢中氢含量为 (0 94～ 1 15 )× 10 -6。叙述了转炉 ,LF(VD) ,连铸的操作实践     

洁净钢精炼实践

从热力学和动力学的角度分析了ASEA -AKF精炼过程 ,并针对洁净钢生产优化了精炼工艺 ,得到了稳定的产品质量 ,使高碳钢 (w (C) =0 .5 5 %～ 0 .6 5 %)中w (T .O)平均 <15× 10 -6、w([Si]) <0 .0 10 %,w(夹杂 )总量为 0 .0 0 2 3%。     

Thermodynamics and Phase Equilibria for Ce,Y in the Presence of O,S in Ni-base Solutions

The deoxidation,desulfuration,deoxysulfuration constants and the standard Gibbs energies(inJ mol~(-1))of formation of the following rare earth compounds as the equilibrium phases in Ni-base solutionsare given:Ce_2O_3:lgK=-(6.0729×10~4/T)+16.50 △G~0=-1.162460×10~6+315.84TCe_2O_2S:lgK=-(5.1450×10~4/T)+12.46 △G~0=-9.84850×10~5+238.50TCe_2S_3:lgK=-(7.2232×10~4/T)+27.98 △G~0=-1.382600×10~6+535.55TY_2O_3:lgK=-(4.2572×10~4/T)+7.74 △G~0=-8.14920×10~5+148.16TY_2O_2S:lgK=-(3.3146×10~4/T)+3.85 △G~0=-6.34460×10~5+73.72TY_2S_3:lgK=-(1.22487×10~5/T)+55.78 △G~0=-2.344630×10~0+1067.76TInteraction coefficients between Ce.Y and O are also given:e_o~(?)=-(3.33451×10~5/T)+149.7 e_O~(?)=-(1.63437×10~5/T)+71.8The phase equilibria for Ni-Ce-S-O and Ni-Y-S-O solutions at 1600℃ provide the basis for pre-dicting the sequence and type of Ce and Y equilibrium phases formed in Ni-base solutions.The formulascontrolling the morphology of inclusion formed in liquid Ni by Ce or Y addition are also given.     

Amiloride-insensitive Na+-H+ exchange: a candidate mediator of erythrocyte Na+-Li+ countertransport

Erythrocyte Na+-Li+ countertransport shows an increased activity in essential hypertension and diabetic nephropathy, but its nature remains unknown. This amiloride-insensitive membrane transport may not be a mode of operation of the amiloride-sensitive NHE1, the only Na+-H+ exchange isoform found in human erythrocytes. Whether an independent, although unknown, amiloride-insensitive isoform mediates Na+-Li+ countertransport is unclear. Na+-H+ exchange activity was measured in acid-loaded erythrocytes. Dimethylamiloride, a specific inhibitor of Na+-H+ exchange and phloretin, a known inhibitor of Na+-Li+ countertransport, gave a reduction in H+-driven Na+ influx (by 31 and 37%, respectively). This effect was additive, and a 66% reduction in H+-driven Na+ influx was found in the presence of both inhibitors. Internal acidification, a stimulus for Na+-H+ exchange, enhanced Na+-Li+ countertransport activity (from 287 +/- 55 to 1213 +/- 165 micromol x Lcell(-1) h(-1), mean +/- SEM, P = 0.003). This transport remained sensitive to phloretin under both conditions. Conversely, external acidification decreased Na+-Li+ countertransport activity (as expected for a Na+-H+ exchanger). Competition between internal H+ and Li+ or Na+ for a common binding site was present. Finally, similar kinetic parameters for external Na+ characterized Na+-Li+ countertransport and the phloretin-sensitive component of H+-driven Na+ influx. These findings suggest that both Na+-Li+ countertransport and the amiloride-insensitive, phloretin-sensitive component of H+-driven Na+ influx can be mediated by a previously unrecognized novel amiloride-insensitive Na+-H+ exchange isoform in human erythrocytes.     

Solubilities of Pb+2, Bi+3, Sb+3, and Cu+1 sulfides in (NaCl+KCl+Na2S) melts

Solubilities of common metal sulfides have been determined in the (NaCl+KCl) eutectic melt with and without Na₂S. A novel gas-phase equilibrium technique has been used for PbS, Bi₂S₃, and So₂S₃, and an improved liquid phase equilibrium technique for Cu₂S, which eliminates the errors due to physical entrapment of the sulfide phase and segregation on quenching, enabling precise measurements to be made. Solubilities in the (NaCl+KCl) eutectic melt were determined as a function of temperature in the rante 700° to 950°C, and were found to be small. The partial molar heats of mixing of the sulfides in the eutectic melt have been calculated from the solubility measurements, to be 13.3, 31.4, 37.1, and 49.0 kcal for PbSs), Sb₂S₂(l), and Cu₂S(s), respectively. Sodium sulfide addition was observed to enhance these solubilities, the effect being largest for Cu₂S followed by Sb₂S₃, Bi₂S₃, and PbS. This effect is explained qualitatively. It was observed that PbS and Sb₂S₃ obey Henry's law up to saturation in (NaCl+KCl+Na₂S) melts. O. P. MOHAPATRA, formerly Graduate Student, University of Toronto     

用APACHE+PHP+MYSQL实现网站自动更新

在分析建立自动更新网站必要性的基础上,较详细地说明了如何利用APACHE+PHP+MYSQL工具实现网站自动更新中的权限控制、资料上传、自动更新,并给出了网页的部分源代码.     

Combustion in Layered Ni + Al and Ti + Al + C Powdered Mixtures

Russian Journal of Non-Ferrous Metals - This study is devoted to the technology of producing cermet coatings using self-propagating high-temperature synthesis (SHS). The importance of the study is...