Cu50Zr42Al8块状非晶合金的变温晶化行为研究

研究了Cu50Zr42Al8大块非晶合金在连续升温过程中的晶化行为.结果表明,随升温速度的加快,玻璃转变温度Tg、晶化起始温度Tx、晶化峰值温度Tp都向高温区移动,过冷温度区△Tx扩大;运用Kissinger法分别计算出玻璃转变激活能Eg为417.19 kJ/mol、晶化起始激活能Ex为332.18kJ/mol、晶化峰的激活能Ep为327.70kJ/mol;并运用FWO法计算晶化阶段激活能Ex,随晶化量的增大,阶段激活能呈逐渐减小的趋势,且在最初的阶段(晶化量小于5%),激活能迅速减小.分析表明,Cu50Zr42Al8块体非晶合金具有良好的热稳定性.     

Zr57Cu15.4Ni12.6Al10Nb5块体非晶合金晶化行为研究

用示差扫描量热仪（DSC）研究了Zr57Cu15.4Ni12.6Al10Nb5块体非晶合金的匀速升温晶化与等温晶化的晶化行为。在匀速升温晶化方式下，用Kissinger法与Ozawa法获得了块体非晶合金的激活能，对第一晶化峰分别为320．5kJ／mol和316．6kJ／mol，对第二晶化峰分别为324．5kJ／mol和320．5kJ／mol。该非晶合金的晶化表现出明显的动力学效应。在等温晶化方式下，用Johnson-Mehl-Avrami方程获得了晶化的Avrami指数为1．61，表明非晶合金的晶化受原子扩散控制。     

铁基块体非晶合金的制备及其晶化动力学

采用工业用原材料在铜模吸铸条件下制备了直径为2 mm的Fe50Co7Ni13Zr10B20块体非晶合金.利用X射线衍射仪(XRD)、差分扫描量热计(DSC)对铸态样品的结构、非晶合金的热稳定性、晶化动力学行为进行了研究.该合金的玻璃转变温度Tg、初始晶化温度Tx1、过冷液相区△Tx1约化玻璃转变温度Trg分别为804 K、875 K、71 K和0.59.采用连续加热方法对其晶化动力学进行了研究,得到其玻璃转变激活能和晶化峰激活能分别为339.2 kJ/mol和326.4 kJ/mol,表明合金具有强的热稳定性.由VFT方程拟合获得该非晶合金的脆性参数m为23.     

ZrCuAlNb大块非晶合金的热稳定性

利用电弧炉+铜模吸铸的方法制备了Zr46.3Cu43.4Al8.3Nb2(at%)块体非晶合金。利用示差扫描量热仪(DSC)研究了合金的热稳定性,利用Kissinger方法计算了其特征温度表观激活能,利用Doyle方法计算了其局域激活能。结果表明,Zr46.3Cu43.4Al8.3Nb2块体非晶合金具有良好的热稳定性。各特征温度的表观激活能分别为:玻璃转变激活能(Eg)为302.7 kJ/mol、晶化起始激活能(Ex)为445.853 kJ/mol、晶化峰值激活能(Ep)为389.20 kJ/mol。局域激活能随着晶化体积分数的增加而显著减小。     

Cu64Zr36非晶合金的晶化动力学

利用单辊急冷法制备了CH64Zr36非晶合金，使用盐浴等温退火并用DSC和XRD研究了其晶化过程、玻璃转变和晶化动力学。结果表明：CH64Zr36非晶合金的晶化过程为：非晶一非晶＋Cu10Zr7→Cu10Zr7＋CuZr2。该合金的玻璃转变和晶化激活能分别为433．7kJ／mol和603kJ／mol。     

Mg60Cu30Y10块体非晶合金的变温晶化行为

采用示差扫描量热仪(DSC)得到Mg60Cu30Y10块体非晶合金在不同加热速率下的DSC曲线。利用Losocka、Kissinger以及Doyle方法研究了Mg60Cu30Y10块体非晶合金的非等温晶化动力学。结果表明:Mg60Cu30Y10块体非晶合金具有良好的热稳定性。通过Kissinger方法计算得到的其玻璃转变激活能(Eg)、晶化激活能(Ex)以及晶化峰值激活能(Ep)分别为160.07 kJ/mol、136.11和145.19 kJ/mol。随着加热速率的提高,各特征温度值向高温端移动。局域晶化激活能随着复合材料晶化体积分数的增加先增大后减小。     

Zr43Cu50Al7块体非晶合金的结构弛豫和晶化研究

在不同加热速率下应用差示扫描量热法(DSC)研究了Zr43Cu50Al7块体非晶合金的结构弛豫现象和晶化行为,得到了满意的晶化曲线.由晶化曲线得到弛豫峰与玻璃转变温度(Tg)、晶化起始温度(Tx)和晶化峰温度(Tp).Zr43Cu50Al7非晶合金的过冷液相区ΔTx达76.2 K,具有较强的玻璃形成能力.对所得到的弛豫峰作了初步的研究,并运用Kissinger法和Deloy法分别计算出玻璃转变激活能Eg、晶化起始激活能Ec、晶化峰的激活能Ep和晶化阶段激活能Ex.结果表明Zr43Cu50Al7块体非晶合金具有良好的热稳定性.     

Co含量对Ti-Zr-Be-Cu块体非晶合金热稳定性的影响

采用铜模法制备了Ti35Zr30Be27.5xCu7.5Cox (x=3.5,7.5,11.5,摩尔分数)系列块体非晶合金,并采用差示扫描量热仪(DSC)和X射线分析(XRD)研究了不同Co含量对其热稳定性的影响.结果表明,随着加热速度的提高,3种非晶合金的玻璃转变温度、晶化开始温度和峰值温度均向高温区移动,说明该系列合金的玻璃转变和晶化均为动力学过程.用Kissinger方法计算出的玻璃转变激活能(Eg)以及晶化激活能(Ex)分别随着Co含量的增加而增大,当Co含量为11.5％时,其Eg和Ex分别为207.8 kJ/mol和238.1 kJ/mol.     

块体非晶合金Cu58 Zr30 Ti10 Sn2的形成与晶化行为研究

采用铜模吸铸法制备了直径为2～3mm的圆柱状Cu60-xZr30Ti10Snx（x=0、1、2）块体非晶合金。用X射线衍射（XRD）和差式扫描量热仪（DSC）研究了非晶合金的结构、热稳定性和晶化特征，非晶合金Cu60-xZr30Ti10Snx的特征温度Tg、Tx、△Tx=（Tx-Tg）均与Sn含量相关。块体非晶合金Cu58Zr30Ti10Sn2的Tg为703．9K、Tx为755．5K、△Tx约为51．6K。这些特征温度随DSC升温速率的增大，不断向高温区偏移，其中晶化行为的这种动力学效应比其玻璃转变的更为显著。由Kissinger法获得的块体非晶合金Cu58Zr30Ti10Sn2的玻璃转变激活能Eg为3．30eV、晶化激活能Ex为3．17eV、第一晶化峰激活能Ep1为2．82eV、第二晶化峰激活能Ep2为3．13eV。由Ozawa法获得的各激活能比Kissinger法的相应数值稍偏低，但趋势是一致的。     

Mg-Cu-Y合金非晶形成能力及热稳定性分析

利用单辊甩带法快速凝固技术制备Mg65Cu25Y10合金非晶薄带,采用X射线衍射仪、差示扫描量热仪对非晶薄带的玻璃形成能力及其热稳定性进行了分析,通过Kissinger法和Ozawa法计算了Mg65Cu25Y10非晶合金的表观激活能。结果表明,Mg65Cu25Y10非晶合金具有较强的玻璃形成能力,其过冷液相区宽度值在42⁵6 K之间,约化玻璃转变温度为0.52。Mg65Cu25Y10非晶合金的热稳定性较高,其玻璃转变激活能和起始晶化激活能分别为352.0、137.5 kJ/mol,两个晶化峰值激活能分别为61.2 kJ/mol和81.4 kJ/mol。Mg65Cu25Y10非晶合金的玻璃化转变和晶化均具有动力学效应,随着升温速率提高,非晶合金的特征转变温度向高温区移动。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

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。     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

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.     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

The Mirror with Patterns of Auspicious Animals and Grapes——Exquisite cast mirror and the technology of surface tin-enrichment by rubbing-in and infiltration of tin-rich powder

<正>Bronze mirrors were used by the Chinese people before the introduction of the glass mirror.Only after it was replaced by the glass mirror did the bronze mirror gradually retreat from people's lives.Different styles of bronze mirrors were made in different historical periods,particularly in the Warring States Period,the Han and Tang Dynasties,which were the three peaks of the development of bronze mirror arts in ancient China.The casting techniques were exquisite.The surface of the bronze mirror was smooth and bright enough to reflect one's image,and there were scarcely any casting defects on the mirror surface.On the back of the bronze mirror,there were rich depictions of Arts and Humanities,and the ornamentations were also     

The 9th China International Diecasting Congress & Exhibition

The 9th China International Diecasting Congress ＆ Exhibition was held on July 22-24, 2014 at Shanghai New International Expc Centre. This exhibition was the most successful over the years, with over 6890 visitors and 155 exhibitors, and the exhibition area increased by 30% from 9,500 square meters in 2012 to 12340 square meters. Die casting enterprises from a total of 24 countries and regions, including China mainland, Chinese Taiwan and Hong Kong, South Korea, Japan, Germany, India, Thailand, Malaysia, the United States, Russia, Australia, Iran, Ukraine, Brazil, Colombia, Singapore, Austria, Canada, Croatia, France, Turkey, United Kingdom, Vietnam, attended the congress and exhibition.     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

正The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining produc-     

RARE METALS Volume Contents

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