富铁Fe-Nd-Al系大块非晶合金的制备及其性能

利用普通的铜模铸造制备了一系列富Fe的Fe-Nd-Al块状非晶合金,采用X射线衍射仪、差示量热扫描仪、振动样品磁场仪和Instron万能材料试验机研究了Fe-Nd-Al块状非晶合金的热稳定性、室温磁性和力学性能。结果表明：Fe50Nd35Al15、Fe45Nd40Al15和Fe42.5Nd42.5Al15块状非晶合金的△Tm（△Tm=Tm-Tx）和晶化开始温度（Tx）与熔点（Tm）的比值分别为106、90和64K及0.88、0.90和0.93;其临界尺寸分别为1.5、3和4mm。此外,随Fe含量的减少,大块非晶的非晶形成能力和硬磁性能提高,但其力学性能有所下降。     

Nd对Mg65Cu22Ni3Y10非晶形成能力及热稳定性的影响

利用楔形铜模铸造法成功制备了Mg65Cu22Ni3Y10-xNdx(x=0、2、4、5、6、8)块体非晶合金,采用XRD、DSC研究了Nd对该合金体系热稳定性和非晶形成能力(GFA)的影响。结果表明,当x=2、4时,Nd的添加可有效提高该合金的GFA和热稳定性;当Nd含量为2%(摩尔分数)时,合金具有最高的过冷液相区(ΔTx=61.5K)及最好的热稳定性;当x=5时,尽管过冷液相区(ΔTx=48.5K)最窄,但此时合金具有最强的非晶形成能力(Trg=Tg/Tl=0.568)和临界厚度(δmax=3.8mm);随着Nd的进一步增加(x>5),合金的玻璃形成能力降低。     

Zr55Al10Cu30Ni5-xPdx块状非晶合金的玻璃形成能力和热稳定性

用铜模铸造方法制备了不同尺寸的Zr55Al10Cu30Ni5-xPdx(x=0,1,3,5)块状非晶合金，采用X射线衍射（XRD）、扫描差热分析（DSC）和透射电镜（TEM）分别为Zr55Al10Cu30Ni5-xPdx块状非晶样品的结构、热稳定性和微观组织进行了研究。结果表明：x=1时，合金具有最高的过冷液相区（高达100K）及最大的热稳定性，而对合金的玻璃形成能力影响不大，这说明用适量的Pd代表Zr55Al10Cu30Ni5合金中的Ni会提高合金的热稳定性；x=3时，合金的热稳定性有所提高，但降低了合金的玻璃形成能力；x=5时，非晶合金的热稳定性和玻璃形成能力同时降低。     

Fe75-xMxHf3Y2B20(M=Co, Nb; x=0, 4)块体非晶合金的制备及其热、软磁性能

采用单辊法和铜模铸造法制备了Fe75-xMxHf3Y2B20(M=Co,Nb;x=0,4 at%)合金系的非晶薄带和非晶棒样品,并测试了该非晶合金系的差示扫描量热曲线、X射线衍射图谱和软磁性能.结果表明:少量的Nb或Co替代Fe75Hf3Y2B20中的Fe元素,合金的热稳定性和玻璃形成能力可得到明显的提高;其中Fe71Nb4Hf3Y2820的过冷液相区宽度△Tx高达75 K,约化玻璃转变温度Trg为0.58,直径达4 mm,饱和磁感应强度为0.97～1.08 T,该非晶合金同时具有较大的热稳定性、较强的玻璃形成能力和较好的软磁性能.     

Y对Cu基非晶合金形成能力和腐蚀行为的影响

采用铜模吸铸法制备出成分为(Cu50Zr45Al5)100-xYx(x=0,1,2,3,4,5)的合金试样。利用X射线衍射,金相显微镜,差热分析和电化学极化曲线的方法研究了Y对Cu-Zr-Al系非晶合金的结构、玻璃形成能力和腐蚀行为的影响。结果表明,适量Y的添加提高了非晶合金的玻璃形成能力和热稳定性,当Y含量为2%时合金的过冷液相区宽度为ΔTx=Tx-Tg=64K,约化玻璃转变温度Trg=Tg/T1=0.601,玻璃形成能力γ=Tx/(Tg+T1)=0.409(Tg,Tx,T1分别为非晶合金的玻璃转变温度,晶化开始温度和熔化温度)。非晶合金在3.5%的NaCl溶液中的耐蚀性随Y含量的增加而降低。     

Nd60Fe20Al10-xCo10Bx非晶合金的结构、磁性能和晶化行为的研究

采用示差扫描量热法(DSC)，X射线衍射(XRD)和振动样品磁强计(VSM)研究了Nd60Fe20Al10-xCo10Bx(x=0，2，5)大块非晶合金的结构、磁性能和晶化行为。结果表明：Nd60Fe20Al10-xCo10Bx非晶合金在晶化前既没有发生玻璃转变也没有过冷液相区；Nd60Fe20Al10Co10合金的DSC曲线上在360℃～475℃之间有1个宽的放热峰，加入2at％～5at％的B后该放热峰消失。铸态Nd60Fe20Al10-xCo10Bx(x=0，2，5)大块非晶合金在室温具有硬磁性。随B含量的增加，合金的内禀矫顽力显著增加，而饱和磁化强度和剩磁则有所下降。B的加入使Nd60Fe20Al10Co10合金的晶化行为发生明显变化。     

Fe-Co-Ni-Zr-Mo-W-B块体非晶合金的玻璃形成能力与热稳定性

采用铜模铸造法,可以制备出直径为3 mm的非晶圆柱棒.结合差热分析、X射线衍射和透射电镜分析测试结果,从动力学和结构学等方面阐述了Ni元素对Fe58Co10-xNixZr10Mo5W2B15(x=0,3,4,5,6,摩尔分数,%)合金系玻璃形成能力和热稳定性的影响.结果表明:Ni元素含量的微量变化可以明显改善Fe58Co10-xNixZr10Mo5W2B15(x=0,3,4,5,6)合金系的玻璃形成能力;当Ni含量达到4%时,Fe58Co6Ni4Zr10Mo5W2B15具有最佳的玻璃形成能力,晶化温度(Tx)、玻璃转变温度(Tg)、过冷液相区宽度(△Tx)、玻璃形成能力判据Trg和y分别为887 K、957 K、70 K、0.590 2和0.400 4.     

一种新型Nd基块体非晶合金

在铜模铸造条件下制备了直径2．5mm的Nd61Fe30Zn9块状非晶合金．在普通DSC条件下，没有观察到这种合金的玻璃转变温度，晶化温度为730K，比Nd60Fe30Al10非晶合金的晶化温度低约70K，因此该合金的热稳定性较低．熔化行为分析表明，合金Nd61Fe30Zn9的熔化过程为单峰吸热过程，且熔化区间仅为54K，说明该合金的成分接近合金的共晶成分，但母合金的自然凝固组织不具有共晶凝固特点，表现为粗大的枝晶状组织．讨论了成分和组织对合金非晶形成能力的影响．     

Gd含量对Cu50Zr42Al8非晶形成能力及热稳定性的影响

利用铜模铸造法成功制备了锥形Cu50-xZr42Al8Gdx(x=0、1、2、3、4、5)块体非晶合金,采用XRD、DSC研究了Gd的添加对该合金体系非晶形成能力(GFA)和热稳定性的影响.结果表明,x=2,4时的合金非晶形成能力最大,非晶合金的临界尺寸为6～7 mm,这也说明适量Gd的添加可以促进非晶的形成能力.加入稀土元素2%Gd后,非晶合金具有最好的热稳定性(ATx=69K),但随着Gd含量的增加,过冷液相区△Tx逐渐减小.本实验中,约化玻璃转变温度Trg和参数γ不是十分的吻合,而具有相对小的△Tx值的合金却有着相对大的非晶形成能力,这意味着非晶合金的非晶形成能力与其热稳定性没有必然的联系.     

Nd对块体Mg-Cu-Y-Nd非晶合金玻璃形成能力的影响

在非真空熔炼条件下采用工业纯原材料和负压铜模吸铸法制备Mg65Cu25Y10-xNdx(x=0,2,4,6,8,10)棒状试样,利用差示扫描量热(DSC)和X射线衍射(XRD)等方法分析Nd对Mg-Cu-Y-Nd非晶合金玻璃形成能力的影响。结果表明:Nd的含量(x)为0,4,6成分的合金试样具有完全非晶态组织,且x=4时具有最大的玻璃形成能力,其约化玻璃转变温度(Trg)为0.592,过冷液相区宽度(ΔTx)高达66 K;当x为2,8,10时,由于合金成分明显偏离共晶成分,玻璃形成能力降低,试样只含有少量非晶,且主要呈晶体组织特征。     

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.     

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。     

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.     

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.