在位生成TiB2／Al—Si—Mg复合材料的组织与性能

结合LSM法和MCR法原位反应生成TiB2粒子增强Al-Si-Mg复合材料。研究发现,原位生成TiB2粒子呈等轴状且尺寸＜1um,大都均匀分布在共晶组织中,与共晶Si交织在一起,在α（Al)中只有少量的TiB2粒子。原位TiB2粒子可明显强化Al-Si-Mg复合材料,且随着TiB2粒子数量的增加,强化效果也随之提高,而且延伸率也略有升高,如6％TiB2/Zl104复合材料室温拉伸强度可达296MPa,延伸率为5．5％,热处理（T6)可将共晶Si由原先的连续棒状变为孤立的颗粒状,大幅度提高材料抗拉强度,使6％TiB2/Zl104复合材料室温拉伸强度达386MPa,而材料仍属于韧性材料。     

原位生成TiB_2/ZL102复合材料的研究

研究了熔体直接反应原位生成TiB2 粒子强化ZL10 2复合材料。结果表明 :原位生成的TiB2 粒子呈等轴状 ,尺寸都小于 1μm ,大部分弥散分布在共晶区内 ,而在α Al内几乎不存在TiB2 粒子 ;TiB2 粒子的生成显著提高材料的室温抗拉强度 ,当w(TiB2 )粒子为 7%时 ,σb 提高了 2 5 % ,而且材料仍为塑性材料     

TiB2/Al-CU复合材料微观组织和力学性能研究

采用原位反应合成法制备了TiB2/ZL2002复合材料.对复合材料的微观组织观察表明,增强相TiB2颗粒主要分布于晶界上,与CuAl2相交织在一起,尺寸在1μm左右,呈现圆球形.铸态下复合材料室温抗拉强度随着TiB2含量的增多而明显提高,伸长率则有降低的趋势.T6处理后,复合材料中析出相与增强相分布较均匀,6%TiB2/ZL202抗拉强度达到325 MPa.     

Bi变质原位自生Mg2Si/Al复合材料的研究

采用纯Bi对原位自生Mg2Si/Al复合材料进行变质;采用金相显微镜等观察了变质前后材料的微观组织;测试了材料的拉伸性能;并对变质前后合金的断口形貌进行了分析.结果表明,在原位自生Mg2Si/Al复合材料中添加适量的金属Bi对初生Mg2Si和共晶Mg2Si能够同时起到良好的变质作用,初生Mg2Si的形貌由粗大的树枝状或多角形块状转变为细小的块状,尺寸由70 μm减小到6 μm,而共晶Mg2Si则由粗大的片状转变为细小的片状、纤维状或点状.经1.0％的Bi变质后,材料的拉伸性能得到大幅度提高,抗拉强度从175 MPa提高到260MPa,提高了48.6％,伸长率从3.5％提高到7.0％.     

原位自生TiB2/Al复合材料的组织与力学性能

采用钛盐与硼盐反应法成功制备原位自生TiB2/纯Al复合材料。利用扫描电子显微镜、透射电子显微镜和拉伸试验机研究不同粒子含量(质量分数为1%、2%和3%)对复合材料组织和力学性能的影响。结果表明:原位生成的TiB2粒子有矩形、近圆形和六边形三种形貌,尺寸为200~500 nm;粒子与Al基体界面洁净无反应层。随着粒子含量的增加,复合材料的强度随之升高,而伸长率则随之降低;当TiB2含量为3%时,屈服强度和抗拉强度分别达到78.1 MPa和102 MPa,相比于纯Al分别提高58%和43%,而伸长率降至32.5%,下降了24%。断口分析表明:随着TiB2粒子含量的增加,粒子团聚机率增加,在拉伸过程中,裂纹在粒子团聚处萌生并扩展,导致材料的塑性降低。     

(Al2O3+TiB2)/ZL202复合材料的制备和力学性能

采用原位熔体反应合成法制备了(Al2O3 TiB2)/ZL202复合材料.用电子探针对复合材料的微观组织进行观察.结果表明:增强相TiB2颗粒主要分布于晶界上,与CuAl2相交织在一起,尺寸在1 μm左右,呈现圆球形,Al2O3颗粒约在3 μm左右,呈现规则的颗粒或圆球状,且彼此分离,界面干净.对铸态复合材料室温抗拉强度和硬度的测试发现,两相颗粒增强的复合材料都较单一颗粒增强复合材料要高.经过T6处理后,(Al2O3 TiB2)/ZL202复合材料的抗拉强度由221.0 MPa提高至339.6 MPa,提高幅度达53.67%,其延伸率降低至2.60%.     

原位反应-液态搅拌法ATS/Al复合材料的显微组织与力学性能

用光学显微镜和透射电镜对液固原位反应-液态搅拌法制备的Al3Ti-TiB2-SiCp/Al13Si2CuNiMg混杂增强铝基复合材料(简记为ATS/Al)的显微组织特征进行了观察分析,用MTS800电液伺服试验机测定了T6热处理态该复合材料室温和350 ℃时的拉伸性能,并与基体合金的组织与性能进行了对比.结果表明,ATS/Al复合材料的Al晶粒和初生Si尺寸明显减小,Al基体中的位错密度增大.原位反应生成的TiB2尺寸细小(约为1 μm),与Al晶体间存在[011-]Al∥[010]TiB2位向关系.ATS/Al复合材料的室温与350 ℃拉伸断裂强度分别提高到375 MPa和175 MPa,比基体合金提高了10%和20%,而延伸塑性接近基体合金.本文对原位反应-液态搅拌法ATS/Al复合材料的多机制协同增强机理进行了讨论.     

多元氧化物和铝原位反应制备铝基复合材料的组织和性能

采用SEM、EDS、XRD、TEM和拉伸强度测试等研究Al2O3粒子增强的ZL109铝基复合材料。结果表明:多元氧化物和铝原位反应生成的Al2O3粒子尺寸细小,粒径约为0.1μm,在基体中弥散分布,与基体存在共格关系,(001)α(Al)//(010)α-Al2O3,[110]α(Al)//[001]α-Al2O3。原位反应中生成的金属间化合物经T6处理后,以Al5FeSi、FeCr、Mg2Si、Al3Ni、Al2Cu和Al7Cu4Ni相的形式存在于基体中,使得复合材料在300℃的拉伸强度达到163.4 MPa,较基体的提高7.9%。随Al2O3粒子含量的增加,25℃时,复合材料断口断裂方式由韧性断裂转变为解理断裂,再到穿晶断裂;而300℃时,断口断裂转变方式为脆性断裂到延性断裂。     

原位生成Al3Ti和TiB2增强铝基复合材料的研究

采用原位反应法制备（Al3Ti＋TiB2）／ZL101原位复合材料，测试其室温力学性能，并通过OPM、TEM观察其微观组织。结果表明，原位复合材料经过热处理后，抗拉强度、伸长率以及布氏硬度分别提高了30．9％、17．1％、29．6％。原位复合材料增强相TiB2和Al3Ti弥散分布在α-Al中，Al3Ti呈棒状，几乎与α-Al完全共格；TiB2呈粒状。（TiB2＋Al3Ti）／ZL101原位复合材料强韧化的主要机制是细晶强化和弥散强化。     

多增强相原位复合材料的微观组织及增强机制

采用原位反应法制备(ZrB2+Al3Zr+TiB2+Al3Ti)/ZL101原位复合材料,测试了其室温力学性能,并通过金相显微镜、TEM观察复合材料中增强相的形貌、结构和分布.结果表明,该复合材料经过热处理后,抗拉强度为352.8 MPa,伸长率为4.3%,硬度为117 HB,分别较ZL101基体材料提高了34.7%、4.9%、19.4%.金相显微组织分析表明:复合材料的α-Al枝晶晶粒尺寸较ZL101明显细化,原位复合材料的共晶硅尺寸也较基体中细小得多;透射电子显微分析表明:4种增强相整体分布较为均匀,且与基体的界面光滑洁净;复合材料主要强化机制为细晶强化、固溶强化、弥散强化.     

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.     

Rheology Feature of Simple Metal Melt

The rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.     

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.