冶炼工艺对GH871合金裂纹扩展速率的影响

对GH871合金的裂纹扩展速率及扩展行为的研究结果表明由于真空冶炼降低了弱化合金晶界的有害元素Pb含量,显著降低了该合金的裂纹扩展速率。     

Activation Energy for Superplastic Flow Above Critical Temperature of Die Steels

 Some commercial cold working die steels GCr15 and CrWMn with ultra fine grain size were chosen as tested materials to research the activation energy for superplastic flow at different temperatures and strain rates above critical temperature. Based on the Arrhenius equation, the activation energy for superplastic flow is evaluated. The activation energy at constant strain rate is estimated by the logσt vs 1/T relationship. The results show that the activation energy is usually small under the conditions of optimal flow. The characteristics of superplastic deformation of steels above the critical temperature were also analyzed.     

浅谈温度控制在轧制品种钢过程中的作用

介绍了温度控制在生产品种钢过程中的作用 ,分析了温度控制在轧制品种钢过程各阶段的关键点 ,提出了存在的问题及其解决方法     

原料润磨对球团氧化活化能的影响

本文通过阿仑尼乌斯公式对磁铁矿原料润磨前后球团氧化反应的活化能进行了研究 ,研究表明 :原料不润磨 ,球团氧化反应活化能为 3 3 96kJ/mol;原料经润磨后 ,球团氧化反应活化能为 3 1 68kJ/mol。这说明润磨降低了球团氧化反应的活化能     

变形量对Cu—4Al合金再结晶激活能的影响

研究了变形量对Cu-4Al合金再结晶激活能的影响,根据公式G＝G0exp^(-Q/RT)计算出再结晶激活能（Q）。结果表明：Cu-4Al合金再结晶激活能随其变形量的增加而减小。     

短流程铸造工艺改进节能效果的探讨

介绍了短流程铸造工艺改进方法,重点阐述了短流程铸造工艺与传统铸造工艺的比较,实现短流程铸造工艺改进的方法,以及工艺改进实例的节能效果。     

温度对电解二氧化锰工艺影响的研究

电解Mn的影响因素多于电解MnO2,所以试图研究在低温下电解MnO2来解决同槽电解Mn和MnO2温度差异问题。通过对比试验,研究以钛板为阳极在MnCl2-HCl溶液中和在Mn-SO4-H2SO4溶液中、以钛钌板为阳极在MnCl2-HCl溶液中温度对电解二氧化锰的电流效率和槽电压的影响,结果表明以钛钌板为阳极在MnCl2-HCl溶液中电解MnO2,低温下(45℃时)就具有低且稳定的槽压(-2.7 V)和高的电流效率(45℃时,ηA70%;55℃时,ηA90%)。X衍射试验表明:以钛钌板为阳极在MnCl2-HCl溶液中45℃电解沉积的物质是γ型二氧化锰。     

不同温度和光照对紫叶酢浆草生长的影响

[目的]研究不同温度和光照条件下紫叶酢浆草的生长情况.[方法]选取3、6、9月和0、25%、50%、75%4个遮阴度环境下的紫叶酢浆草鳞芽进行交叉试验,形成12个处理区,30 d后调查紫叶酢浆草叶柄长度,第二年观察花期、开花量、叶色以及病虫害情况.[结果]春、秋季紫叶酢浆草生长最快;温度对紫叶酢浆草生长影响较大但对其花期影响不大;光照对紫叶酢浆草的花量和叶色影响较大,当遮阴率25%时对紫叶酢浆草生长最为有利;在高温条件下紫叶酢浆草易发生叶斑病和红蜘蛛危害,强烈阴蔽条件下易发生蚜虫和蜗牛危害,[结论]温度22℃、遮阴率25%是紫叶酢浆草生长的最佳环境.     

High Temperature Deformation Behavior of 4340 Steel: Activation Energy Calculation and Modeling of Flow Response

The 4340 steel is extensively utilized in several industries including automotive and aerospace for manufacturing a large number of structural components. Due to the importance of thermo-mechanical processing in the production of steels, the dynamic recrystallization (DRX) characteristics of 4340 steel were investigated. Namely, hot compression tests on 4340 steel have been performed in a temperature range of 900–1200 °C and a strain rate range of 0. 01–1 s^?1 and the strain of up to 0. 9. The resulting flow stress curves show the occurrence of dynamic recrystallization. The flow stress values decrease with the increase of deformation temperature and the decrease of strain rate. The microstructure of 4340 steel after deformation has been studied and it is suggested that the evolution of DRX grain structures can be accompanied by considerable migration of grain boundaries. The constitutive equations were developed to model the hot deformation behavior. Finally based on the classical stress-dislocation relations and the kinematics of the dynamic recrystallization; the flow stress constitutive equations for the dynamic recovery period and dynamic recrystallization period were derived for 4340 steel, respectively. The validity of the model was demonstrated by demonstrating the experimental data with the numerical results with reasonable agreement.     

轧钢工序能耗影响因素分析及节能措施

轧钢生产中加热温度对工序能耗有重要影响。在检测和统计轧钢工序能耗的基础上,对不同加热温度下的吨钢燃耗、吨钢电耗和吨钢烧损做了分析统计,并计算了不同加热温度下的工序能耗。轧制设备、产品质量和电力供应允许的情况下,降低钢坯加热温度可以降低轧钢工序能耗。     

高温红外辐射涂料的节能效果试验研究

分析了高温红外辐射涂料的节能原理,介绍了研制的KTW高温红外辐射节能涂料在实验室、工业锅炉、工业炉窑上的节能试验效果.该涂料成本低,施工工艺简单,涂层发射率稳定,耐热震稳定性良好,使用寿命长,综合效益明显.     

Effect of Nb on Austenite Recrystallization in High Temperature Deformation Process

By analyzing the stepped test pieces with optical microscope,the influence of the technological parameters including rolling temperature and reduction on the austenite recrystallization fraction of steel with Nb content of 0.08% deformed at high temperature processing was studied,and the deformed austenite recrystallization figures of the test steel were obtained.The result indicates that when the reduction is 60%,the critical temperature of complete recrystallization is 1070 ℃ and the borderline temperature of non-recrystallization is 900 ℃.In contrast with general HSLA steel,the recrystallization and non-recrystallization temperatures are respectively 120 ℃ and 100 ℃ higher than those of ordinary HSLA,so the steel with high content of Nb has better hot processing performance because Nb has great function of holding back recrystallization.     

低温拜耳法管道化预热溶出器的节能改造

某厂在建厂初期采用的是新蒸汽直接加热压煮罐间断溶出的氧化铝生产工艺,能耗高,经济性较差。随后自行设计建设的单套管管道化预热溶出器,自动化程度低,二次乏汽没有得到充分利用。在此基础上,又设计建造了三套管管道化预热溶出器,革除了原单套管预热溶出器的不足之处,蒸汽消耗显著降低。     

MWCNTs特征对MWCNTs/Al复合材料组织及性能的影响

采用粉末冶金法制备多壁碳纳米管(MWCNTs)增强铝(Al)基复合材料(MWCNTs/Al),研究MWCNTs的特征对MWCNTs/Al复合材料显微组织结构及性能的影响。采用X线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和拉伸实验对复合材料进行性能测试。结果表明:经过球磨混合的复合粉末中没有碳化铝(Al_4C_3)相,通过烧结和热挤压后出现Al_4C_3相。与长碳纳米管(L-MWCNTs)和短碳纳米管(S-MWCNTs)相比,镀镍碳纳米管(Ni-MWCNTs)在复合材料中分散更均匀,与Al基体的结合性更好,所得到的复合材料硬度和抗拉强度较高,抗拉强度可达到247 MPa,是纯Al的4倍。     

太阳能光伏非碳高温冶炼实验及能量研究

提出了"太阳能光伏非碳冶金"的概念,根据研究需要,确定了其实验系统构成及参数,设计制造了1kg公称容量的实验炉。进行了"太阳能光伏非碳冶金"高温冶炼实验,确定了工艺参数,并进行了冶炼过程物料和热量的衡算。实验结果表明,所设计的系统满足冶炼要求,有较好的稳定性及可操作性。通过砽的计算可知太阳能光伏技术利用是一个将其自身砽值提高的过程。     

Effect of Structural State and Temperature on Crack Generation and Propagation Resistance in Pipe Steels

Metallurgist - Comparative research of microstructure and properties of different strength classes of plate steels produced by controlled rolling with accelerated cooling is performed. Standard...     

脆性温度区工艺对中厚板裂纹的影响

为了解和认识中厚板连铸坯高温脆化及内裂纹的形成、扩展的机制,对某些代表钢种进行60 0～1 0 5 0℃温度范围高温拉伸试验,测试试件断裂时的断面收缩率,作出脆化曲线,并分析热加工过程中化学成分、工艺参数等与高温区金属脆化行为的关系。为改进连铸工艺制度,在再加热及轧制过程中预防裂纹的危害性提供重要的参考依据。     

ZrVFe吸气剂激活过程研究

通过X射线光电子能谱仪（XPS）对ZrVFe吸气剂的激活过程进行了研究。结果表明：暴露于大气的吸气剂表面覆盖着一层CO2,O2及碳氢化合物,合金表面中的锆和钒主要以氧化态存在。当吸气剂置于高真空进行激活时,钒的氧化物在较低的温度（200～300℃）下被还原,并且还原比例高于锆的氧化物。在激活温度为300℃至340℃的过程中,表面大量的ZrO2和VO2逐渐减少而被还原为亚氧化物和金属态。激活过程还导致了在表面近金属态锆的富集,以及部分金属碳化物的生成。     

工艺参数对氧气高炉能耗的影响规律

建立了氧气高炉煤气不循环利用流程,炉身喷吹循环煤气流程和炉缸喷吹循环煤气流程数学模型,分析了工艺参数对氧气高炉能耗的影响,结果表明：煤气不循环利用流程一次能耗远远高于煤气循环利用流程,不适合进行工业化生产;金属化率对氧气高炉能耗影响很大,金属化率每升高5％,吨铁焦比降低约37kg;煤气循环利用流程各煤气量匹配要合理,炉...