电镀锡机组软熔导电辊粘锡失效模拟研究

粘锡是宝钢电镀锡机组 2 # 软熔导电辊失效的主要原因 ,通过模拟 2 # 软熔导电辊的工况条件 ,研究了影响导电辊粘锡主要因素。结果表明 ,提高淬水槽水温和导电辊冷却水温 ,都促使导电辊辊面粘锡 ,加剧降低辊面粗糙度。此外提高淬水槽中的锡含量 ,也促使导电辊粘锡。采取带钢出淬水槽后加快带钢冷却和降低导电辊冷却水温等措施 ,可减轻导电辊粘锡 ,提高导电辊寿命。     

一种可焊性半光亮镀镍工艺

目的解决镀镍层可焊性不良的问题,使得光电子器件外壳镀镍层可焊性满足回流焊要求,并且保存半年后可焊性不降低。方法以氨基磺酸镍为体系,考察温度、p H值、电流密度与沉积速率的关系,采用回流焊和浸润法对镀层可焊性进行表征,并考察镀层的质量、结合力及盐雾性能指标。结果镀液体系在比较宽泛的电流密度和温度范围内,都能得到可焊性优良的镀层,其沉积速率随电流密度的增大呈线性增加。浸润法和回流焊接试验表明,镀层可焊性满足要求。在稳态湿热(45℃,RH=95%)环境中48 h或恒温烘烤(150℃,1 h)后,镀层可焊性仍均满足要求。结论在电流密度1~5 A/dm2,p H值3.2~4.4,温度40~55℃的条件下能得到优良的可焊性镀层,满足回流焊对镀层可焊性的要求,并且放置半年后可焊性不降低。     

Preparation of 5N high purified indium by the method of chemical purification-electrolysis

The application of indium requires high purity indium as material. 5N high purity indium had been prepared by the method of a combination of chemically smelting and electrolysis. Smelting time was l 0 min, the abstraction rate of cadmium was 80%-90% when used solution of I2-KI and glycerine to smelt indium. 4N metal indium was used as anode, high purity indium as cathode, In:(SO4)3-H2SO4 system as electrolyte, and In content is 100 g/L, pH 2-3 and current density 80- 100 A/m:. The thallium was removed by smelting indium using 15% Nt-LCl-glycerine solution for 20 min and tin by smelting indium using NaOH and NaNO3 for 20 min. The removed rate of tin was 60%.The product quality of indium reached national standard of 5N high purity indium.     

Vacuum Carbothermal Reduction for Treating Tin Anode Slime

In this work, a process of vacuum carbothermal reduction was proposed for treating tin anode slime containing antimony and lead. During vacuum carbothermal reduction, the antimony and lead were selectively removed simultaneously by reducing and decomposing the less volatile mixed oxide of lead and antimony into the more volatile Sb₂O₃ and PbO. Then the tin was enriched in the distilland and primarily present as SnO₂. Crude tin was obtained via vacuum reduction of the residual SnO₂. The results showed that 92.85% by weight of antimony and 99.58% by weight of lead could be removed at 850°C for 60 min with 4 wt.% of reductant and air flow rate at 400 mL/min corresponding to the residual gas pressure of 40 Pa–150 Pa. Under these conditions, an evaporation ratio of 52.7% was achieved. Crude tin with a tin content of 94.22 wt.% was obtained at temperature of 900°C, reduction time of 60 min, reductant dosage of 12.5 wt.%, and a residual gas pressure of 40 Pa–400 Pa. Correspondingly, the direct recovery of tin was 94.35%.     

提高臂架销轴疲劳寿命的方法

针对目前混凝土泵车臂架销轴疲劳寿命较低的现状,研究销轴不同材料、油口加工工艺及热处理对销轴疲劳寿命的影响。结果表明,在油口加工工艺、销轴热处理工艺相同的前提下,30CrMnTi钢销轴疲劳寿命较40Cr钢长39%,较40CrMnMo钢长16%。而30CrMnTi钢销轴油口倒角由90°改为120°,粗糙度由12.5μm提高到6.3μm,且经过滚压处理时,疲劳寿命可提高52%。适当的热处理,如回火温度由200℃提高到560℃时,疲劳寿命可再次提高30%。     

莱钢H型钢轧机轧辊气雾冷却试验

针对用水直接冷却轧辊存在冷却不均、轧件断面温差大等问题，在莱钢小型H型钢生产线上进行了轧辊气雾冷却的试验，结果表明，气雾冷却能使轧辊轧制量提高约25%，H型钢腹板内冷却水减少约2/3，H型钢表面最大温差减少14～16℃。     

质子-电子混合导体SrCe_(0.95)Tm_(0.05)O_(3-δ)的电性能研究

采用高温固相法制备了质子-电子混合导体SrCe_0.95Tm_0.05O_(3-δ)材料.使用X射线衍射仪、扫描电子显微镜分别对1600 ℃烧结10 h后的混合导体晶型、微观形貌进行了研究.应用交流阻抗谱法测试了空气、氢气、氩气3种不同气氛中混合导体的电导率.结果表明:所制备的混合导体为单相致密斜方晶钙钛结构,气氛对晶粒电导率影响不大,而对晶界和总电导率有明显影响.800 ℃空气、氢气和氩气气氛中总电导率分别为4.65×10~(-3),3.41×10~(-3),1.87×10~(-3) S·cm~(-1).     

在低转变温度氯化胆碱-乳酸混合物中电沉积锡层的研究

将氯化胆碱、乳酸按一定比例混合制备了低转变温度混合物,随后在混合物中加入SnCl2获得电沉积液。将尺寸为4.5cm×3.0cm的铁片分别在50℃和60℃的电沉积液中沉积了锡层。借助于电导率测定仪、扫描电镜、X射线衍射仪和电化学工作站研究了电沉积温度对电沉积锡层的微观形貌、成分、相组成和耐蚀性的影响。结果表明:与50℃电沉积的锡层相比,60℃电沉积的锡层的电导率较大,晶粒较粗,孔隙较多,导致其腐蚀电势负移,腐蚀电流密度增大。     

球墨铸钢材料性能研究与优化

针对球墨铸钢轧辊在使用过程中出现的开裂失效问题,从材料化学成分、组织方面对开裂原因进行了分析。结果表明:材料化学成分及热处理工艺参数控制不当导致的组织异常是轧辊开裂的主要原因,材料化学成分中C、Si、Mn质量分数分别为1.40%、1.50%、0.70%,热处理温度为950℃的试棒组织和性能最佳,抗拉强度和伸长率分别为989 MPa和2.0%,对应轧辊的使用寿命最长。     

时效工艺对纳米结构2297铝锂合金力学性能与微观组织的影响

采用535 ℃×2 h固溶制度,将热锻态2297铝锂合金固溶水淬后冷轧,冷轧压下量为95%,然后将轧制样品在不同温度(120~190 ℃)和时间(0~80 h)范围内进行时效处理。采用拉伸、扫描电镜(SEM)和透射电镜(TEM)等测试方法,分析时效温度和时间对铝锂合金组织与性能的影响。结果表明:时效前的大塑性变形能获得纳米结构组织,能促进T₁相均匀细小地析出,缩短合金达到峰时效的时间,最终成功制备了高强高塑性铝锂合金。在120~140 ℃温区内时效时,时效温度越高,达到峰时效的时间越短、强度越高。140 ℃达到峰时效时间缩短为40 h,此时合金的抗拉强度、屈服强度和伸长率分别为525 MPa、478 MPa和7.7%,主要强化相为细小的T₁相。在170~190 ℃温区内时效时,时效温度越高,达到峰时效的时间越短,但抗拉强度与屈服强度迅速下降。170 ℃时效8 h达到峰时效状态,此时合金的抗拉强度、屈服强度和伸长率分别是503 MPa、462 MPa和5.0%,主要强化相仍为T₁相,但已经明显粗化。     

Residual stress in quenched 7075 aluminum alloy thick plates

1　INTRODUCTION70 75isoneoftheprecipitation hardenedalu minumalloysmainlyusedasplateandforgingsintheaerospaceindustry .Itshighstrengthisachievedthroughaquenchingoperationwherethematerialisrapidlycooledfromthesolutionheattreatmenttem perature(4 75℃ )toroomtemperature ,whichcancausetheadverseeffectofintroducingresidualstress ,leavingthematerialunsuitableforfurthermachiningoperationsandforservice[13] .Residualstressinthequenchingoperationforaluminumalloysisusuallystudiedbynumericalprediction…     

防止合金冷硬铸铁轧辊上辊颈裂纹的措施

针对影响上辊颈热裂纹的主要因素,采用工频炉熔炼铁液严格控制浇注温度和化学成分(质量分数)等相应的措施,使上辊颈的废品率下降了70%左右,生产出合格的合金冷硬铸铁轧辊上辊颈铸件。     

热轧带钢冷轧基料表面氧化铁皮的成因与控制措施

分析了热轧带钢表面氧化铁皮的成因、特点及结构组成,通过合理安排生产计划、控制工作辊辊面质量、优化终轧和卷取温度、提高钢卷冷却速率等措施,使冷轧基料产品的酸洗速度由原来约30-40m／min提高至60-70m／min,酸洗时间缩短了40％～50％。     

稀土对A572.Gr65钢夹杂物及低温冲击性能的影响

为了研究不同含量混合稀土(Ce/La)对A572.Gr65钢低温冲击性能的影响,对A572.Gr65钢在-40 ℃和-60 ℃下进行低温冲击试验,并使用OM观测显微组织,利用SEM结合EDS观测夹杂物及断口形貌并检测其化学成分。结果表明,稀土可以明显变质A572.Gr65钢中夹杂物,将不规则的Al₂O₃和Al₂O₃-CaO夹杂物变质为球状稀土夹杂物;夹杂物尺寸由5 μm减小至不足2 μm。加入稀土后钢的低温冲击性能有明显提升,当稀土含量达到0.0057%时,-40 ℃冲击吸收能量由未添加稀土的317.4 J升至343.6 J,提升了8.2%;-60 ℃冲击吸收能量由未添加稀土的288.0 J升至328.1 J,提升了13.9%。     

硫酸铅在碳酸钠-硝酸钠熔盐中的脱硫转化

利用TG-DSC技术分析了PbSO4在Na2CO3-NaNO3熔盐体系中的脱硫转化过程的行为特征,通过XRD、SEM、EDS等手段研究了焙烧温度、原料配比、助剂加入量等因素对PbSO4脱硫转化过程及其产物形态的影响。结果表明:NaNO3能够对PbSO4脱硫转化过程起到显著的强化作用;提高焙烧温度、增加Na2CO3和NaNO3的用量均能促进PbSO4脱硫转化反应的进行。在物料摩尔比为PbSO4∶Na2CO3∶NaNO3=1∶1.1∶0.2,焙烧温度为600℃,保温时间为1 h的条件下,PbSO4可完全脱硫,转变为粒径约为1～3μm的β-PbO粉体,产物中未观察到其它杂相。     

添加氧化铁高效热解脱除氰化钠

提出采用氧化铁催化热解高效除氰.采用XRD、DSC-TG、化学分析等手段对不同条件下添加和无添加氧化铁高效脱除氰化钠的机理进行研究.未添加氧化铁时,空气条件下,氰化钠在587.4℃开始发生分解;氩气条件下,氰化钠在879.2℃开始发生分解.添加氧化铁时,氩气条件下,大约60％的氰化钠在350℃热解30 min时发生分解...     

N-105合金在NaNO_3和Na_2O_2沉积盐层中的高温氧化行为

用X-射线衍射、SEM及EDAX方法研究了N-105合金在700℃,NaCO3和Na2O2沉积盐层中的高温氧化行为.结果表明,合金在NaNO3沉积盐层中的腐蚀比Na2O2沉积盐层中更为严重.     

Fundamental study on utilization of tin and zinc-bearing iron concentrate by selective chlorination

The feasibility and technologies of comprehensive recovery of tin, zinc, arsenic and iron from the complex iron ores by selective chlorination roasting were studied by thermodynamic analysis and roasting experiments. Investigation shows that the product pellets with the compression strength of 2 625 N/P, the tumble index of 97. 26%, the abrasion index of 1. 35%, tin, arsenic and zinc residue of 0. 043%, 0. 046% and 0.058% respectively can be achieved if bailing a concentrate containing 0.39 % tin, 0.40% arsenic and 0.28% with addition of 8% coke breeze and 0. 5% CaCl2 and roasting the pellets at 1 060 - 1 080℃ for 40 min. The volatilization of tin, arsenic and zinc is 91.75 %, 93.42 % and 81.12 % respectively. The performances of the product pellets are able to meet the requirements of blast furnace ironmaking.     

EQUILIBRIUM PHASE DIAGRAMS IN SYSTEM CuO-PbO-Ag

ＥＱＵＩＬＩＢＲＩＵＭＰＨＡＳＥＤＩＡＧＲＡＭＳＩＮＳＹＳＴＥＭＣｕＯ－ＰｂＯ－Ａｇ￥ＳＨＡＯＺｈｏｎｇｂａｏ;ＬＩＵＫｕｉｒｅｎ;ＭＥＮＧＢｏ;ＬＩＹｉｎｇ;ＹＡＮＧＹｕｑｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ,Ｎｏｒｔｈｅａｓｔｅｒｎ...     

NaNO3对含Cl^—衣康酸溶液中316L不锈钢的缓蚀作用

通过失重法和电化学法以及表面膜ＸＰＳ分析，研究了ＮａＮＯ３对含Ｃｌ＾－衣康酸介质中３１６Ｌ不锈钢的缓蚀性能，结果表明：溶液中一定量的ＮａＮＯ３可使不锈钢的点蚀电位显著提高，有效地撸制点蚀，缓 蚀效率达８１－９５％温度、