Fe_(41)Co_7Cr_(15)M_(0.14)Y_2C_(15)B_6非晶合金的力学性能和磁性

正P.Rezaei Sahreza等人研究退火时Fe_(41)Co_7Cr_(15)M_(0.14)Y_2C_(15)B_6非晶合金力学性能和磁性变化,研究结果表明,退火过程该非晶合金晶体中含有Fe_(23)(B_4C)6、Mo_3Fe_3C及Mo_3Co_3C等相。928℃退火时这些相的体积分数增加到32.3%。借助压痕试验研究本试验的块状非晶合金的力学性能,通过分段式研磨得到Palmqvist裂纹的裂纹系统种类。通过提高退火温可以同时提高硬度和刻痕韧性。增加结晶相体积分数,也     

晶化对CoFeBSiNb非晶合金组织及磁性能的影响

采用铜模吸铸法制备直径为2 mm的Co_(47.6)Fe_(20.4)B_(21.9)Si_(5.1)Nb_5非晶合金。利用X射线衍射仪(XRD)、差示扫描量热仪(DSC)、振动样品磁强计(VSM)和显微硬度计研究了晶化对合金相结构、磁性能及显微硬度的影响。结果表明:Co_(47.6)Fe_(20.4)B_(21.9)Si_(5.1)Nb_5非晶合金退火后的晶化过程为非晶相→非晶相+Fe_(23)B_6相→Fe_2B+Fe_3Si+Co_7Fe_3+未知相。该合金的饱和磁化强度随退火温度的升高先降后升,在1123 K退火后最高达到93.14 A·m~2·kg~(-1)。合金晶化后具有极高的显微硬度,在1073 K退火后显微硬度高达1721 HV。     

THERMAL STABILITY AND PERPENDICULAR ANISOTROPY OF AMORPHOUS TbFeCo FILMS

The perpendicular anisotopy,coercivity and Kerr rotation angle of the amorphousTb_(32)Fe_(54)Co_(14) films were studied.The X-ray,electron diffraction,XPS and AES profile con-firmed that no obvious change in their amorphous structure and oxygen concentration is ob-served after annealing at 100℃,while their properties alter evidently under bending stress.Itseems to be believed that the perpendicular anisotropy in the Tb_(32)Fe_(54)Co_(14) films mainly arisesfrom the induced stress during preparation and the magnetostriction coupling stress,as wellas,the thermal instability of the film relates closely to the stress relaxation during annealing.     

旋转磁场退火对非晶态合金中感生磁各向异性的影响

研究了旋转磁场退火对非晶态合金Fe_4Co_(66)Ni_2T工_2Si_(10)B_(16),Fe_5Co_(70)Si_(15)B_(10)及Fe_(40)Ni_(40)B_(20)的磁各向异性的影响。用磁转矩方法测定了在不同旋转速率的磁场作用下合金中感生磁各向异性在等温退火(260—280℃)过程中的变化。实验结果指出,在旋转磁场退火过程中,原存于试样中的感生磁各向异性K_u值随退火时间单调下降,其下降曲线和磁场的旋转速率无关;而由旋转磁场退火所感生的磁各向异性,在一般实际条件下,可以忽略不计.这个实验结果可以成功地用本文提出的理论进行解释.     

EFFECT OF ROTATING MAGNETIC FIELD ANNEALING ON INDUCED ANISOTROPY OF AMORPHOUS ALLOYS

研究了旋转磁场退火对非晶态合金Fe_4Co_(66)Ni_2T工_2Si_(10)B_(16),Fe_5Co_(70)Si_(15)B_(10)及Fe_(40)Ni_(40)B_(20)的磁各向异性的影响。用磁转矩方法测定了在不同旋转速率的磁场作用下合金中感生磁各向异性在等温退火(260—280℃)过程中的变化。实验结果指出,在旋转磁场退火过程中,原存于试样中的感生磁各向异性K_u值随退火时间单调下降,其下降曲线和磁场的旋转速率无关;而由旋转磁场退火所感生的磁各向异性,在一般实际条件下,可以忽略不计.这个实验结果可以成功地用本文提出的理论进行解释.     

退火工艺对Fe_(91.63)B_(1.27)Si_(7.09)非晶带材腐蚀性能的影响

采用真空电弧炉铜模铸造法制备出Fe_(91.63)B_(1.27)Si_(7.09)非晶带材,并用失重法对比研究了非晶带材在HCl、H_2SO_4溶液里的腐蚀行为;采用X射线衍射仪和光学显微镜对该非晶带材的相组成、晶化过程及试样的腐蚀形貌进行了研究,并综合分析了退火工艺对Fe_(91.63)B_(1.27)Si_(7.09)非晶带材耐腐蚀性能的影响。结果表明:Fe_(91.63)B_(1.27)Si_(7.09)非晶带材在20%H2SO_4溶液中的耐蚀性比45钢高300倍。非晶合金晶化程度随退火温度升高而提高,带材的腐蚀速率取决于退火温度。在500℃以下退火时,Fe_(91.63)B_(1.27)Si_(7.09)非晶带材腐蚀速率变化不大;在500℃以上退火时,Fe_3Si相和Si_4Cu_(15)相析出,腐蚀速率明显增大;当退火温度上升到700℃时,已由非晶态完全转变成晶态,腐蚀速率大幅度提高。     

FeCo基薄带气流中应力退火感生的磁结构

采用单辊快淬法制备Fe_(36)Co_(36)Nb_4Si_(4.8)B_(19.2)(FeCo基)合金非晶薄带,流动气体中外加张应力电流退火的方法制备不同磁结构的样品.采用阻抗仪测量各样品的纵向驱动巨磁阻抗(LDGMI)效应曲线.通过比对分析不同应力退火样品的LDGMI曲线特征参量(半高宽、最大巨磁阻抗比值)与驱动频率之间关系曲线的差异,以及比对不同腐蚀深度样品的差异,依据趋肤效应原理及LDGMI曲线与材料磁各向异性关系的理论,揭示了FeCo基非晶薄带应力退火感生磁结构的特性及机理.     

磁场退火对纳米晶合金软磁性能的影响

利用真空退火,将非晶合金纳米晶化,并通过XRD试验手段验证了其纳米晶结构,研究了磁场退火对纳米晶合金软磁性能的影响。研究表明,在外加磁场条件下,对Fe_(74.5)Cu_1Nb_2Si_(13.5)B_9、(Fe_(0.5)Co_(0.5))_(73.5)Cu_1Nb_3Si_(13.5)B_9和Ni_(25)(Fe_(0.5)Co_(0.5))_(48.5)Cu_1Nb_3Si_(13.5)B_9纳米晶合金进行二次热处理,可以不同程度地减小合金的饱和磁致伸缩程度。然而,磁场退火后纳米晶合金在较低温度下的初始磁导率出现了不同程度的降低,原因可以归结为:在磁场退火的过程中,感生出的单轴各向异性增加了合金总的各项异性。     

旋转磁场退火消除非晶合金磁各向异性的研究

利用测定磁化功之差法,研究了旋转磁场退火(RFA)温度T_(RFA)、保温时间t_(RFA)和冷速V_(RFA)对非晶Fe_5Co_(73)Si_(10)B_(12)合金磁各向异性K_Q的影响规律,发现在T_(RFA)=400℃,t_(RFA)=30min和V_(RFA)=6℃/min条件下,RFA可使K_Q降低约80%.K_Q减少的原因是由于RFA驱散了应力-磁致伸缩耦合与原子对方向有序引起的磁各向异性的结果.     

MODIFICATION OF MAGNETIC ANISOTROPY OF AMORPHOUS ALLOYS BY ANNEALING IN ROTARY MAGNETIC FIELD

利用测定磁化功之差法,研究了旋转磁场退火(RFA)温度T_(RFA)、保温时间t_(RFA)和冷速V_(RFA)对非晶Fe_5Co_(73)Si_(10)B_(12)合金磁各向异性K_Q的影响规律,发现在T_(RFA)=400℃,t_(RFA)=30min和V_(RFA)=6℃/min条件下,RFA可使K_Q降低约80%.K_Q减少的原因是由于RFA驱散了应力-磁致伸缩耦合与原子对方向有序引起的磁各向异性的结果.     

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.