热处理制备Cr2O3-石墨插层化合物的研究

以三氧化铬(CrO3)与石墨为原料,利用真空热处理方法制备了三氧化二铬(Cr2O3)石墨的插层化合物(GICs).运用X射线衍射(XRD)分析石墨插层化合物.结果表明:经热处理后,在1400℃时CrO3与石墨形成了纯5阶的石墨的插层化合物.XRD分析表明,对网状层面结构的天然石墨,可以利用物理的方法使一些非碳反应物(原子、分子、离子、或粒子团)插入石墨层间,从而改变石墨的层面结构,使产物出现新的物理性质和化学性质.X射线光电子能谱(XPS)分析和表征了Cr离子以3价的形式存在于石墨插层化合物中.     

热处理制备Cr2O3-石墨插层化合物的研究

以三氧化铬（CrO3）与石墨为原料，利用真空热处理方法制备了三氧化二铬（Cr2O3）石墨的插层化合物（GICs）。运用X射线衍射（XRD）分析石墨插层化合物。结果表明：经热处理后，在1400℃时CrO3与石墨形成了纯5阶的石墨的插层化合物。XRD分析表明，对网状层面结构的天然石墨，可以利用物理的方法使一些非碳反应物（原子、分子、离子、或粒子团）插入石墨层间，从而改变石墨的层面结构，使产物出现新的物理性质和化学性质。X射线光电子能谱（XPS）分析和表征了Cr离子以3价的形式存在于石墨插层化合物中。     

Zr元素对9mass％Cr-ODS合金中析出相分布特征及硬度的影响

采用机械球磨的方式制备了Fe-9Cr-1.5W-3Y2O3和Fe-9Cr-1.5W-3Zr-3Y2O3合金粉,并对其进行了真空等温热处理.利用X射线散射(X-ray diffraction,XRD)、X射线吸收精细结构谱(X-ray absorption fine structure,XAFS)、小角度X射线散射(small angle X-ray scattering,SAXS)等分析了球磨及真空等温热处理不同时间后合金中析出相的变化情况,同时测量了合金的硬度.XRD实验结果表明当合金中添加锆元素后,除铁索体衍射峰外热处理过程中还形成了ZrO2相及Y4Zr3O12相,而在不含锆元素的合金中只检测到Cr2O3相的存在.XAFS实验结果表明当添加锆元素后,合金的XAFS曲线发生改变,不同于纯钇元素及纯氧化钇样品.SAXS实验结果说明含锆元素的合金经1100℃真空等温热处理1h后,其氧化物析出相的分布密度最高,为9.27× 1021/m3.无论合金化学成分如何变化,球磨后合金的硬度最高,添加锆元素后有利于提高合金的硬度.     

P11O钢表面韧性FeAl渗层的低温制备

通过在摩尔比为2∶1的AlCl3-EMIC(氯化1-甲基3-乙基咪唑)室温离子液体中电沉积铝镀层加低温热处理的方法,在P110钢表面进行低温渗铝.用金相显微镜(OM)、扫描电子显微镜(SEM)、能量散射X射线谱仪(EDS)和X射线衍射(XRD)研究了渗层的组织结构.结果表明:为保证P110钢基体的硬度,热处理温度应低于620℃,而渗铝速度在高于590℃时较快.6 μm铝镀层试样经620℃×24 h热处理,可以得到8μm由韧性FeAl相组成的渗层.     

ZG35Cr24Ni7SiN耐热钢不同温度下的氧化膜特征分析

运用X射线衍射(XRD)和扫描电镜(SEM)等手段对900℃和1 250℃下的ZG35Cr24Ni7SiN耐热钢的氧化膜进行了分析和研究.结果发现,ZG35Cr24Ni7SiN耐热钢900℃下的氧化膜在氧化初期只有一层,为Cr2O3 膜,随着氧化时间的延长,其氧化膜分3层,外层为SiO2膜,中间层为Fe2O3膜,内层为Cr2O3 膜,并且在Cr2O3 膜与基材间存在着一个富镍层,由此具有非常好的抗氧化性.ZG35Cr24Ni7SiN 耐热钢1 250℃下的氧化膜在初期分两层,外层为Mn3 O4/NiFe2O4膜,内层为Mn3O4/Cr2O3/SiO2膜.随着氧化时间的延长变成一层,为Cr2O3/Mn3O4 膜,具有较好的抗氧化性.     

1Cr18Ni9Ti高温氧化行为研究

采用熔模精密铸造法制备1Cr18Ni9Ti耐热不锈钢,用氧化增重法在800℃对1Cr18Ni9Ti耐热不锈钢进行100 h氧化腐蚀实验.采用扫描电镜(SEM)观察其基体组织及各氧化阶段的显微组织彤貌;采用X射线衍射仪(XRD)对该材料最终高温氧化产物进行定性分析.结果表明:ICr18Ni9Ti耐热不锈钢在800℃下的氧化曲线符合抛物线规律;其氧化破坏形式以点蚀为主;最终氧化产物由CrO、Fe2O3(六方)、Fe2O3(立方)、CrTiO3、NiTiO3和Ni3TiO5等混合组成.     

Al0.5CoCrFeNi高熵合金高温腐蚀行为研究

采用真空电弧熔炼炉制备了Al0.5CoCrFeNi高熵合金(下标表示摩尔比).研究了高熵合金在800、900℃的75wt％Na2SO4+25wt％NaCl熔盐中抗高温腐蚀性.利用带有能谱仪的扫描电镜和X射线衍射仪分析高熵合金的腐蚀层形貌、成分和组织结构.结果表明:高熵合金在熔盐中的腐蚀质量损失较严重,随腐蚀温度升高,抗腐蚀性下降;腐蚀层出现明显分层,合金表面生成了疏松多孔的NaFeO2等多种混合氧化物;合金腐蚀过程发生内氧化和内硫化,内层生成Al2O3、CrO3混合氧化物及Cr5S6硫化物.     

含Ag抗菌双相不锈钢表面腐蚀产物的XPS分析

采用X射线光电子能谱技术(XPS)研究了含Ag抗菌双相不锈铸钢在有菌环境中经电化学极化后的表面腐蚀产物。结果表明:添加纯Ag颗粒制备的不锈钢经1150℃固溶处理后,其钝化膜表层中的Ag主要以Ag2+氧化物和游离态的形式存在,Cr主要以CrO2,CrO3和Cr(OH)3形式存在,而添加150～300μm Cu-Ag中间合金颗粒制备的不锈钢经1150℃固溶处理后,其钝化膜表层中的Ag主要以Ag2+,Ag+和Ag2/3+氧化物形式存在,Cr以CrO2、Cr2O3和CrO3等多价态铬氧化物形式共存,且与前者相比,添加150～300μm Cu-Ag中间合金颗粒制备的材料其钝化膜中Cr2O3、钼氧化物和MoO42-的含量更多,而α-FeOOH和Cr(OH)3等氢氧化合物以及水合物的含量更少,表明其钝化膜的稳定性优于添加纯Ag颗粒制备的材料。     

热处理对S30432喷丸不锈钢抗高温水蒸汽氧化性能的影响

将S30432钢喷丸样品进行不同温度热处理,研究样品620℃下在90%H_2O+10%Ar气氛中的氧化行为。采用光学显微镜(OM)观察喷丸形变层组织形貌;通过测量不同时间氧化膜厚度,获得氧化动力学曲线;利用X射线衍射仪(XRD)、扫描电镜(SEM)及能谱仪(EDS)等对氧化产物成分、形貌及结构进行分析。结果表明:热处理过程中S30432钢喷丸样品形变层组织形貌无明显变化;氧化过程中,样品喷丸形变层内晶粒发生再结晶长大;氧化2000 h后,样品喷丸形变层内晶粒尺寸及碎化晶层厚度基本相同。不同温度热处理的S30432钢喷丸样品在高温水蒸汽中均生成由Cr_2O_3、(Fe,Cr)_2O_3、FeCr_2O_4以及少量Fe_3O_4和Fe_2O_3组成的富Cr氧化物薄膜。730～800℃热处理对S30432喷丸不锈钢抗高温水蒸汽氧化性能无明显影响。     

Cr含量对类石墨碳涂层硬度及其价键结构的影响

为了探讨Cr含量对类石墨碳(GLC)涂层硬度的影响机理,采用非平衡磁控溅射离子镀技术,通过调整Cr靶电流,制备出了具有不同Cr含量的GLC涂层.借助显微硬度计测量了涂层的硬度,利用X射线衍射(XRD)和X射线光电子能谱(XPS)分析了涂层的成分、相组成和主元素的价键结构.结果表明,Cr有显著软化GLC涂层的作用.随着Cr含量增加,GLC涂层中的sp3杂化碳的含量持续减小,sp2杂化碳的含量先增后减,而金属铬及碳铬化合物的含量则不断增大.上述因素对GLC涂层的硬度变化均有影响,而涂层中sp3杂化碳的含量随着Cr含量增加持续减小是造成GLC涂层硬度不断降低的主要原因.     

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.     

THERMODYNAMICS STUDY ON THE DECOMPOSITION OF CHROMITE WITH KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

INFLUENCE OF HEAT TREATMENT ON DAMPING BEHAVIOUR OF THE MAGNESIUM WROUGHT ALLOY AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Theoretical Analysis for the Motion and Temperature of Melt Droplets in Spray Degassing Process

The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.     

Growth Kinetics of Single Inclusion Particle in Molten Melts

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.     

An Easy Way to Quantify the Adhesion Energy of Nanostructured Cu/X(X=Cr,Ta,Mo,Nb,Zr) Multilayer Films Adherent to Polyimide Substrates

An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quantitatively estimate the interfacial energy of the nanostructured multilayer films(NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be *5.0 J/m2 for Cu/Cr, *4.1 J/m2 for Cu/Ta,*2.8 J/m2 for Cu/Mo, *1.1 J/m2 for Cu/Nb, and *1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.     

High-Speed Friction Stir Welding of SiC_p/Al–Mg–Si–Cu Composite

A 17 vol% SiCp/Al–Mg–Si–Cu composite plate with a thickness of 3 mm was successfully friction stir welded(FSWed) at a very high welding speed of 2000 mm/min for the first time. Microstructural observation indicated that the coarsening of the precipitates was greatly inhibited in the heat-affected zone of the FSW joint at high welding speed, due to the significantly reduced peak temperature and duration at high temperature. Therefore, prominent enhancement of the hardness was achieved at the lowest hardness zone of the FSW joint at this high welding speed, which was similar to that of the nugget zone. Furthermore, the ultimate tensile strength of the joint was as high as 369 MPa, which was much higher than that obtained at low welding speed of 100 mm/min(298 MPa). This study provides an effective method to weld aluminum matrix composite with superior quality and high welding efficiency.     

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。     

A STUDY OF TEMPERATURE-DEPENDENT VALENCE BOND STRUCTURE OF TITANIUM

On the basis of energy and shape method for the determination of the valence bond (VB) structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is e_c~(2.9907) · (s_c~(0.4980) d_c~(2.4927)) ef1.0093 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K.