高密度烧结金属齿轮的承载能力(英文)

This paper describes a study on the load bearing capacity of newly developed high density sintered metal gears with surface - densification. High density sintered metal gears were hobbed, and then surface - rolled. These gears were case - carburized after surface - rolling. The effect of surface - rolling on the surface property was examined by measuring porosity, and hardness near surfaces of rolled gears. Running tests for these gears were performed. A failure mode and load bearing capacity of high density sintered metal gears and the effects of surface - rolling on the load bearing capacity of sintered metal gears were determined, and the results were compared with those of carburized wrought steel gears and conventional sintered metal gears. The experimental results show that the load bearing capacity of a newly developed high density sintered metal gear with surface - densification is higher than that of a carburized wrought steel gear.     

Design of mould fluxes for continuous casting of special steels

The melting behaviour of mould powder during continuous casting is an important consideration with respect to caster performance, production rate and steel quality. Two important factors, powder composition and carbon addition, are critical to control the properties and melting behaviour of the mould flux. In this study, the effect of different carbonaceous materials on the melting characteristics of mould powders was evaluated. Correlations were established between the structural factors and chemical reactivity of carbon and melting behaviour of mould flux. In addition, two examples are given of the effect of flux composition on casting performance for specific steels. A flux with reasonable basicity and additives was designed for the casting of heat-resistant steel (Incoloy 800) to reduce surface cracks. Another flux was designed for the casting of non-magnetic steel containing high aluminium by partially replacing SiO₂ with Al₂O₃ to limit aluminium oxidation by SiO₂.     

微合金钢连铸表面横裂纹形成机理与控制技术研究现状

表面和角部横裂纹是高强度微合金钢连铸及热轧工艺中最为突出的质量问题,也是国内钢铁企业多年来仍未彻底突破的技术难点。在回顾前人对微合金钢连铸表面横裂纹问题研究的基础上,全面概述了其形成原因、影响因素以及解决措施,重点分析了基体粗大奥氏体晶粒对连铸表面裂纹倾向的影响,揭示了表层组织控制技术的机理及相关参数的制定准则,提出了解决表面横裂纹问题的可行研究方向。     

比表面积对活性氧化铝蒽醌再生能力的影响

活性氧化铝的蒽醌再生量直接影响双氧水的生产及双氧水的价格.通过研究发现,活性氧化铝的比表面积对蒽醌降解物再生活性有显著影响.比表面积小于160 m2/g,蒽醌再生量偏低,但很稳定；比表面积大于260 m2/g,活性氧化铝主要起吸附作用,不能用于蒽醌降解物的再生；比表面积在170～190 m2/g之间,蒽醌再生量较高且稳...     

HAT6065型氰化浸出搅拌槽清水动力学研究

研究了HAT6065型高气泡表面积通量氰化浸出搅拌槽的清水动力学性能,简要分析了4种充气器配置条件下,充气量、空气分散度、溶解氧量、空气保有量等参数之间的关系。结果表明,在4种充气器配置条件下,氰化浸出搅拌槽的空气分散度均较高,可以为确定工业应用条件提供依据。     

A Method for Improving Simulation of PNA Teleconnection Interannual Variation in a Climate Model

The climate modeling community has been challenged to develop a method for improving the simulation of the Pacific-North America (PNA) teleconnection pattern in climate models. The accuracy of PNA teleconnection simulation is significantly improved by considering mesoscale convection contributions to sea surface fluxes. The variation in the PNA over the past 22 years was simulated by the Grid Atmospheric Model of IAP LASG version 1.0 (GAMIL1.0), which was guided by observational SST from January 1979 to December 2000. Results show that heating in the tropical central-eastern Pacific is simulated more realistically, and sea surface latent heat flux and precipitation anomalies are more similar to the reanalysis data when mesoscale enhance ment is considered during the parameterization scheme of sea surface turbulent fluxes in GAMIL1.0. Realistic heat ing in the tropical central-eastern Pacific in turn signifi cantly improves the simulation of interannual variation and spatial patterns of PNA.     

矢量控制同步机在负载扰动时气隙磁场的变化

针对大功率交交变频同步电动机传动系统采用矢量控制技术后的气隙磁链在突加负载时的变化情况进行了研究 ,并结合实际进行仿真 ,证明大功率交交变频凸极同步电动机采用矢量控制技术后 ,其气隙磁链在突加负载时略有增加。     

Thermodynamic Study on BaO-CaO-CaF2 Slags for Dephosphorization of Molten Steel

Phosphorusisadetrimentalelementforsome kindsofsteel.Itiseasilysegregatedinthegrain boundaryduringthesolidificationofsteelresulting inthecold brittleness.Italsoreducesthemechani calpropertyofsteel[1].Inrecentyears,ultralow phosphorus,e.g.below0.01%or0.005%…     

包晶钢连铸保护渣固渣膜粗糙度影响因素

在包晶钢板坯连铸过程中,保护渣固渣膜结构及其性能对减少铸坯表面纵裂起至关重要的作用。采用改进型水冷铜探头获取不同保护渣熔融温度、不同探头浸入时间下的固渣膜。同时采用接触测试、光学显微镜及SEM观察的方法检测、评价保护渣渣膜表面(与水冷铜壁接触面)的粗糙度,并揭示了该渣系条件下保护渣渣膜粗糙度的形成与渣膜结晶(液渣凝固结晶及固渣膜玻璃层中玻璃转变结晶)的关系。研究结果表明,保护渣渣膜粗糙度随凝固时间增长无明显变化。液渣温度对生成渣膜的粗糙度有较大影响,提高液渣温度能明显提高渣膜粗糙度。并且,渣膜表面粗糙度的形成与渣膜结晶过程无明显因果关系,而与渣膜凝固中于固渣膜表面形成的开放气孔有关。     

液渣成分和硅酸二钙颗粒含量对铁水预处理非均相脱磷剂脱磷能力的影响简

 高磷铁水预处理脱磷的难题是脱磷剂用量太大、温降太多,急需研究脱磷能力强的脱磷剂。含有固体颗粒和液渣的非均相脱磷剂比仅含液渣的均相脱磷剂的脱磷能力强很多。为此,针对磷的质量分数为0. 5%的高磷铁水,应用FactSageTM热力学软件优选出脱磷能力强的3种液渣,添加不同数量的硅酸二钙颗粒配制非均相脱磷剂试样,脱磷剂和熔铁在1560℃下反应6h,测定熔铁中的平衡磷含量,用以评价其脱磷能力,然后在1400℃下进行了铁水脱磷预处理试验。研究结果表明,随着硅酸二钙颗粒含量的增加,非均相脱磷剂的脱磷能力明显改善;采用非均相脱磷剂有助于减少渣量和控制反应器内衬的侵蚀;采用非均相脱磷剂对铁水脱磷,仍然需要控制较高的渣铁界面FetO浓度。     

华北陆块北缘燕山铜（钼）成矿带肖家营子-滴答水多金属矿集区成矿条件与找矿方向探讨

肖家营子-滴答水多金属矿集区主要矿床类型为斑岩-矽卡岩型钼（铁铜）矿床。成矿作用受区域承德-北票深断裂及中三家走滑断层、燕山中晚期石英闪长岩斑岩及花岗闪长斑岩、雾迷山组厚层层纹状灰质白云岩的多重控制,已有矿山的深部和外围具有巨大的资源潜力。该区矿产勘查工作应当依据成矿系列理论和该区的成矿特征,类比已知矿床及掌握的找矿信息,开展地质找矿工作。重点围绕着中三家走滑断层及两翼,以斑岩-矽卡岩型铜钼多金属矿床为主攻矿床类型,以综合信息为找矿向导,已知矿床攻深找盲,新区综合勘查,进行深浅结合评价。     

振动、夯打沉管灌注桩在软土地基的应用

采用沉管灌注桩法处理软土地基,经试桩并确定单桩承载力后,采用单打法进行施工。实践证明,采用振动、夯打沉管灌桩法处理软土地基,具有施工简单、工期短、节约材料、经济效益好、能保证工程结构要求及施工机械损坏少等特点。     

低碳带钢异步冷轧的实验研究

本文报导了在一般传动支撑辊的四辊轧机上,改变支撑辊直径实现异步轧制;在此轧机上进行异步轧制低碳带钢可降低轧制压力,减少轧制道次或退火次数,从而提高冷轧带钢生产率。降低其生产成本。     

条形基础作用下半无限大地基极限承载力的刚体弹簧模型有限元法

文章在阐述极限分析的意义和现状后,给出了由日本学者川井忠彦教授提出的“刚体弹簧模型的有限元法（简称ＲＢＳＭＦＥＭ）,并与传统的有限元法相比说明了刚体弹簧模型有限元法在结构极限分析中所具有的优点．文章还运用根据刚体弹簧模型有限元法所研制的程序对条形基础作用下半无限大地基的极限承载力进行了分析,计算结果表明,该方法能解决相关联流动的岩土力学问题．具有计算精度高速度快的优点．     

粉状铝基钎料的高频钎焊工艺研究

介绍了粉状铝基钎料的制备方法,探讨了粉状铝基钎料的工艺性能。从表面张力的角度出发,讨论了粉末粒度、氧含量、加热速度、加热均匀性、钎料钎剂比例等因素对高频铝材钎焊工艺和性能的影响。结果表明:用粒度在150~180μm的粉状铝基钎料钎焊铝材,其钎焊剪切强度较高;加热速度较快、加热盘温度均匀的钎焊效果较好;钎料钎剂的比值在10∶8~10∶10范围钎焊效果较好。     

Modified-EISA synthesis of mesoporous high surface area CeO_2 and catalytic property for CO oxidation

Mesoporous CeO2 particles with high surface area were synthesized using a modified evaporation-induced self assembly(EISA) method which combined citric acid as complexing agent.As-prepared powder and further thermal treatment samples were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),selected area electron diffraction(SAED),Fourier transform infrared spectrometer(FTIR),thermogravimetry and differential thermal analysis(TG-DTA),Brunauer-Emmett-Teller(BET) and Barrett-Joyner-Ha...     

宽厚板包晶钢的保护渣

针对包晶钢的凝固特性,研发了高碱度、高结晶速率、低结晶温度及低热流密度保护渣,并在宝钢3^#连铸机上进行了试验研究.现场试验四个浇次的结果表明,使用改进渣的试验流铸坯无纵裂发生,而使用原渣的对比流铸坯裂纹率达到5%.优化保护渣有效防止了铸坯表面纵裂的发生.     

太钢4350m3高炉合理操作炉型的控制及探讨

 从太钢4350m3高炉对合理操作炉型的认识和调整过程出发,通过分析炉内煤气流分布、透气性指数K值、炉体温度和热负荷等影响和体现操作炉型的参数,探讨大型高炉实现操作炉型有效控制的措施。2011年太钢4350m3高炉通过在炉身中上部进行硬质压入,控制煤气流分布和合理匹配各项操作制度等,成功实现了操作炉型的合理控制和低燃料比生产。     

水泥砼旧路面加铺沥青砼路面层中防反射裂缝的主要措施简析

水泥混凝土路面是我国城市道路的主要类型，在旧水泥混凝土路面上加铺沥青混凝土面层是改善路面使用性能、提高路面使用寿命的主要措施之一。本文简要分析了反射裂缝产生的机理，以及各主要技术措施能防止或延缓反射裂缝的机理。     

提高工业氧化铍产品质量的工艺措施

通过对工业氧化铍生产过程中的沉淀、碱洗、煅烧等工序的工艺操作和技术条件的调整控制，同时加强对比表面积、松装密度及灼失等技术指标的检测，产出的工业氧化铍能满足铍铜母合金生产的需要。