工艺参数对Mo/Cu粉末凝胶注模成形的影响（英文）

采用甲基丙烯酸羟乙酯(HEMA)-1,6-己二醇二丙烯酸酯非水基凝胶注模体系制备了浓Mo/Cu粉末浆料。研究了分散剂用量、单体含量和固相体积分数对浆料流变行为的影响,并讨论了单体含量、单体/交联剂比例、引发剂用量、温度等工艺参数对固化行为和坯体抗弯强度的影响。结果表明,固相体积分数对浆料流变行为的影响最大,其次是引发剂用量和单体含量。随着单体含量的增加和单体/交联剂比例的减小,坯体抗弯强度增加;引发剂用量对坯体抗弯强度的影响较小。根据上述结果,Mo/Cu粉末非水基凝胶注模的合理工艺参数如下:HEMA含量为25%~30%(体积分数),单体/交联剂比例为10:1~15:1,引发剂用量为1.5%~2.5%(体积分数),固化温度在60~80℃之间。     

多孔FeAl非水基凝胶注模成形的可控固化

以铁粉及铝粉为原料,借助旋转粘度计研究了其非水基凝胶体系浆料的固化行为,以获得高质量的坯体。结果表明：引发剂用量、单体体积分数的增加以及固化反应温度的升高会使诱导期与反应期缩短;催化剂用量增加可以显著缩短诱导期时长,但对反应期的影响较小;与此相反,减小单体与交联剂体积比可以缩短反应期,但不改变诱导期的长短。结合浆料稳定性数据,通过调控引发剂及催化剂用量、固化反应温度、单体浓度和单体与交联剂体积比等影响因素,可以控制诱导时间在71~748 s、固化时间在154~714 s之间,从而实现不同尺寸要求和复杂程度产品的可控注模及固化。通过凝胶注模制备的多孔FeAl材料及制品孔隙结构均匀、开孔隙率为57.6 %、孔径小于10 μm、抗压强度可达40.7 MPa,满足烟气分离的需要。     

凝胶注模工艺参数对多孔铝铜合金品质的影响（英文）

通过凝胶注模工艺制备多孔铝铜合金。研究凝胶注模工艺参数如单体含量、交联剂与单体的比例、分散剂和引发体系4个因素对坯体高度、固化时间和坯体品质3个指标的影响。其中分散剂对坯体高度,单体对坯体质量的影响最大。通过分析得出最佳工艺为:单体体积分数10%、交联剂体积分数2%、引发剂体积分数0.2%、分散剂质量1.2 g,在此条件下坯体呈现最好的品质。同时探讨工艺参数消除裂纹和形成孔结构的机理。利用压汞法得出孔直径在10~10000 nm范围内,开孔气孔率达到38.78%。     

90W-Ni-Fe合金的水基体系凝胶注模成型制备及性能

以工业级钨粉、镍粉和铁粉为原料,采用凝胶注模成型技术制备90W-Ni-Fe合金。研究了分散剂含量和固相体积分数对金属浆料黏度的影响,并对素坯的抗弯强度以及脱脂、烧结进行了分析。结果表明,90W-Ni-Fe金属浆料的黏度随着分散剂添加量的增加先降低后升高,随着固相体积分数的增加而增高。坯体抗弯强度随着单体交联剂比例的增大呈现出先升高后降低的趋势,固相体积分数为45%时坯体的抗弯强度最高。素坯脱脂后在1 445℃烧结1.5 h,获得了密度为16.93 g/cm~3的烧结体,其致密度高达98.72%。     

凝胶注模多孔NiTi合金的固化工艺及动力学研究

以氢化脱氢钛粉和雾化镍粉为原始粉末,单体甲基丙烯酸羟乙酯(HEMA)和交联剂1,6-己二醇二丙烯酸酯(HDDA)组成凝胶体系,采用凝胶注模法制备多孔NiTi合金。研究了引发剂(过氧化苯甲酸叔丁酯,TBPB)、催化剂(N,N-二甲基苯胺,DMA)、固化温度及固相体积分数对固化过程的影响。结果表明：随着引发剂及催化剂加入量的增加,固化时间降低,最佳的催化剂用量(质量分数)为1.5%,引发剂用量(质量分数)为2%;固化反应随着固化温度及固相体积分数的增加而加快;根据DSC测试结果,计算得到HEMA-HDDA-TBPB-DMA凝胶体系的固化反应表观活化能为60.15 kJ·mol^-1,反应级数为0.91。在最佳固化工艺条件下,利用固相体积分数为45%的NiTi浆料制备了孔隙率为43.87%、抗压强度为104 MPa,且具有三维连通双级孔隙结构的多孔NiTi合金。     

大尺寸轻型碳化硅质反射镜素坯的凝胶注模成型

利用凝胶注模成型工艺制各了大尺寸轻型碳化硅(SiC)质反射镜素坯.讨论了SiC的颗粒级配、固相含量对浆料性能的影响以及催化剂、引发剂、浆料温度对凝胶时间的影响.结果表明:最佳分散条件下固相含量为65%的SiC水基浆料具备良好的流动性,适于进行凝胶注模成型;引发剂加入量为20 mmol/L浆料,与催化剂的摩尔比为5:1,浆料温度降到15℃时,凝胶时间能够满足注模及成型所需.最终测试了反应烧结后SiC陶瓷的性能.     

凝胶注模技术制备高密度ITO靶材的研究

为了研究ITO粉体凝胶注模技术制备高密度靶材的合理工艺,采用正交试验法,研究了固相含量、分散剂含量、pH值对浆料黏度的影响。结果表明,固相含量和分散剂的质量分数分别为80%和0.08%,pH值为10时,可制备出低黏度的适合浇注的浆料。同时,在制备低黏度、高固相含量(80%)ITO浓悬浮体过程中,研究了单体、交联剂、引发剂含量对凝胶化效果的影响。结果表明,单体、交联剂、引发剂分别为浆料质量的2%、0.05%、0.04%时,可制备出高质量坯体。坯体经70℃干燥、600℃排胶,最后于1570℃烧结后得到密度高达7.12g·cm-3、晶粒尺寸均匀的ITO靶材。     

水基凝胶注Ti-6Al-4V合金坯体

将凝胶注模工艺应用于金属Ti6Al4V合金粉末的成形,研究了高固相含量的Ti6Al4V合金粉末的料浆的制备,比较了金属浆料与陶瓷浆料的不同。结果表明粉末的颗粒形状是影响浆料固相含量的重要因素,浆料的固相含量随分散剂的增加而增加。最后制备出了固相含量为54%(体积分数,下同)的钛合金粉末浆料和形状复杂的坯体。坯体的抗弯强度随气雾化(GA)Ti6Al4V含量增加先增大后减小,随着坯体的固相含量增大而减小。当GA-Ti6Al4V含量为80%,固相含量为50%时生坯抗弯强度最大,为18.5 MPa。     

Ti及Ti-6Al-4V的水基凝胶注模成形研究

将凝胶注模工艺应用于金属Ti及Ti-6Al-4v合金粉末的坯体成形，研究了高固相含量的Ti粉和Ti-6Al-4V合金粉末的料浆的制备。结果表明，用凝胶注模工艺制备出了固相含量为54φ%的钛合金粉末料浆和形状复杂的坯体；粉末的颗粒形状是影响料浆固相含量的重要因素，球形粉末配制成的浆料固相含量最高，近球形次之，片状最低；分散剂柠檬酸铵也可以显著提高浆料的固相含量。     

锶铁氧体胶态振动注模成形技术研究

通过絮凝、振动脱水工艺处理,获得固相体积分数达50%的锶铁氧体浆料,实现了高质量锶铁氧体坯体的胶态振动注模成形.分析了工艺条件对成形过程及样品质量的影响.实验表明:胶态注模成形比凝胶注模成形需要加入更多的单体与交联剂才能得到坯体强度相当的坯体;烧成后的锶铁氧体的剩余磁感应强度为420 mT,矫顽力H_(cb)为270 kA/m,最大磁能积(BH)_(max)为34 kJ/m~3.     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.     

INTRODUCTION TO PATENTS

The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.     

China Foundry Week 2014

China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society （FICMES） each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.     

17th Conference of Hydrodynamic and Electromechanical Control Engineering Call for papers

正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.     

Information for Contributors

正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis     

Preface

<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of     

Information for Contributors

The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.     

Formulas of Tension of Continuous Rolling Process

The development of computer controlled continuous rolling process calls for a mathematical expression that can express the inequality condition of "constant flow". Tension is the link of the continuous rolling process. From the condition of dynamic equilibrium, a differential equation of tension is given out. On the basis of the physical rules established from the industrial practice and experimental studies, the law of volume constancy, the linear relation of forward slip and tension, the state equation of continuous rolling, the formula of dynamic tension, and the formula of static tension have been obtained. These formulae reflect the functional relations between tensions, thickness, roll velocity, and time in the continuous rolling process. It is implied that the continuous rolling process is a gradually steady, controllable, and measurable dynamic system. An assumption of predicting the thickness of a steel plate using these tension formulae is also put forward.