退火Fe_（73．5）Cu_1Mo_3Si_（14．5）B_8合金中α－Fe（S

用ＸＲＤ法研究了退火Ｆｅ７３．５Ｃｕ１Ｍｏ３Ｓｉ１４．５Ｂ８合金中α－Ｆｅ（Ｓｉ）晶化相的有序化过程，结果表明，Ｆｅ７３．５Ｃｕ１Ｍｏ３Ｓｉ１４．５Ｂ８非晶合金经４６０℃×１ｈ退火后，α－Ｆｅ（Ｓｉ）晶化相是具有ＤＯ３结构的有序相，有序畴为球形，直径为６．１ｎｍ，它随退火温度的升高而长大，在５６０℃退火后达１４．０ｎｍ，与α－Ｆｅ（Ｓｉ）晶粒的尺寸相当。此时，α－Ｆｅ（Ｓｉ）的有序度为０．７８。８００℃×１ｈ退火后，α－Ｆｅ（Ｓｉ）的ＤＯ８超点阵线条消失。     

均匀化处理对3004铝合金显微组织的影响

采用光学显微镜， 扫描电子显微镜， 透射电子显微镜， 电子探针Ｘ 射线微区分析仪和定量图像分析仪研究了３００４ 铝合金铸态和均匀化退火态的显微组织以及均匀化退火温度和时间对显微组织的影响。在铸态组织中发现了一种新的富ＭｇＳｉＣｕ 的共晶体。在均匀化退火过程中发生β→α相变和α弥散相的脱溶析出。在试验条件下， 最佳均匀化退火工艺为６１５ ℃，２０ ｈ 。经此工艺处理可获得较均匀的显微组织     

退火温度对Fe73.5Cu1Mo3Si14.5B8合金电阻的影响

研究了退火温度与晶化相结构的关系,讨论了退火温度对Ｆｅ７３．５Ｃｕ１Ｍｏ３Ｓｉ１４．５Ｂ８合金电阻的影响,结果表明,α－Ｆｅ粒子在４６０－５６０℃范围内几乎不长大,但温度高于５６０℃时,晶粒尺寸明显长大;随退火温度的升高,Ｆｅ７３．５Ｃｕ１Ｍｏ３Ｓｉ１４．５Ｂ８合金的电阻率呈下降趋势。     

高合金奥氏体铸造不锈钢析出相及腐蚀行为的研究

高合金奥氏体不锈钢铸态组织中有σ相存在，经８５０～１１２０℃热处理所形成的σ相包括：（Ｆｅ－Ｃｒ）σ相、（Ｆｅ－Ｍｏ）σ相、以及（ＣｒＮｉＳｉ）σ相。８５０℃左右有Ｍ６Ｃ型碳化物和ＮｂＣ析出。该钢经１１５０℃×２ｈ水冷固溶处理后，具有优良的抗均匀腐蚀、晶间腐蚀、点蚀和化学腐蚀性能。     

Nd_2（Fe，Co）_（14）B／Nd_2（Fe，Co）_（17）双相HDDR

研究了由Ｎｄ_２（Ｆｅ，Ｃｏ）_（１４）Ｂ和Ｎｄ_２（Ｆｅ，Ｃｏ）_（１７）双相组成的ＨＤＤＲ高矫顽力磁粉的微观结构及磁性。发现在单相Ｎｄ_２（Ｆｅ，Ｃｏ）_（１４）Ｂ化合物的基础上降低Ｂ含量，导致Ｎｄ_２（Ｆｅ，Ｃｏ）_（１７）相出现，且随Ｂ含量降低该相逐渐增多．适量的Ｎｄ_２（Ｆｅ，Ｃｏ）_（１７）相的存在对用性有一定有益的作用，过量则导致磁性严重恶化，这可能与该相的尺寸和存在形式密切相关．     

高温磁场热处理Alnico8永磁合金组织粗化过程的稳定性分叉

采用透射电镜（ＴＥＭ）和Ｘ射线小角散射（ＳＡＸＳ）技术研究了经８００℃磁场热处理不同时间Ａｌｎｉｃｏ８合金组织的粗化行为，研究表明，合金分解为富Ｆｅ和Ｃｏ以及富Ｎｉ和Ａｌ相，其中富Ｎｉ和Ａｌ相有序，总体而言，组织随处理时间的延长变得愈加均匀细小，这是棒状富Ｆｅ和Ｃｏ粒子在磁场热自理初期短时内迅速粗化至一定尺寸后分解成细小富Ｆｅ和Ｃｏ粒子的结果。发生分解的原因是Ａｌｎｉｃｏ８合金在粗化过程中产生很大     

EFFECTS OF CARBON AND YTTRIUM ON 500℃ AGING EMBRITTLEMENT OF ALLOY Fe-15Cr-4Al

测定了Ｆｅ－１５Ｃｒ－４Ａｌ合金在５００℃的时效脆化动力学，利用内耗，ＴＥＭ，ＥＰＭＡ和ＳＥＭ等手段研究了合金在时效后的组织变化和断裂行为。结果表明，时效脆化第一阶段（０－１００ｈ）主要是碳化物在α相晶界析出的作用，它损害界面结合，降低断裂应力，使塑性在时效０．２５ｈ后消失；第二阶段（１００－１０００ｈ）主要是富Ｃｒ－α＇相均匀析出的作用，它通过强化基体引起二次脆化。含０．２和０．４％的Ｆｅ－１５     

碳和钇对Fe－Cr－Al合金500℃时效脆化的影响

测定了Ｆｅ－１５Ｃｒ－４Ａｌ合金在５００℃的时效脆化动力学，利用内耗，ＴＥＭ，ＥＰＭＡ和ＳＥＭ等手段研究了合金在时效后的组织变化和断裂行为．结果表明，时效脆化第一阶段（０－１００ｈ）主要是碳化物在α相晶界析出的作用，它损害界面结合，降低断裂应力，使塑性在时效０．２５ｈ后消失；第二阶段（１００－１０００ｈ）主要是富Ｃｒ－α＇相均匀析出的作用，它通过强化基体引起二次脆化．含０．２和０．４％Ｙ的Ｆｅ－１５Ｃｒ－４Ａｌ－Ｙ合金在固溶态下无Ｓｎｏｅｋ内耗峰，碳在α相中的浓度低于０．０００７％，这是碳原子被Ｙ_２Ｆｅ_（１７）相俘获的结果．因此，含钇合金在５００℃时效时不发生晶界碳化物析出，时效１０００ｈ后塑性无明显变化．     

La_1－zRz（Fe_1－x－yCoxAly）_（13）金属间化合物磁熵变特性研究

本文对用Ｆｅ、Ａｌ替代Ｃｏ的Ｌａ（Ｆｅ（０．７３）－ｘＣｏｘＡｌ（０．２７））（１３）系和用Ｒ（Ｃｅ，Ｐｒ，Ｎｄ，Ｓｍ，Ｄｙ，Ｇｄ）替代Ｌａ的Ｌａ１－ｚＲｚ（Ｆｅ（０．７１）Ｃｏ（０．０２）Ａｌ（０．２７））（１３）系的结构、磁性及磁熵变特性进行了研究。实验发现，Ｌａ（Ｆｅ（０．７８）－ｘＣｏｘＡｌ（０．２７））（１３）系的晶体结构均保持ＬａＣｏ（１３）的立方结构，每３ｄ原子的饱和磁矩与其电子数ｎｄ的关系在富Ｃｏ侧符合刚性能带模型，而在富Ｆｅ侧则与该模型不符。当ｘ＝０．０２时该化合物的居里温度在室温并有较高的磁熵变△ＳＭ，在１．１１ＭＡ／ｍ（１．４Ｔ）磁场下的（△ＳＭ）ｍａｘ为１３ｋＪ／ｍ３·Ｋ。对于Ｌａ１－ｚＲｚ（Ｆｅ（０．７１）Ｃｏ（０．０２）Ａｌ（０．２７））（１３）系，实验发现除Ｃｅ外，其它稀土元素均不能与Ｌａ、Ｆｅ、Ｃｏ、Ａｌ形成１：１３相，而是形成了２：１７相。     

添加钴和铜的Nd－Fe－B型烧结磁体

添加钴和铜的Ｎｄ－Ｆｅ－Ｂ型烧结磁体为提高Ｎｄ－Ｆｅ－Ｂ型磁体的矫顽力，改善磁体的温度稳定性和耐蚀性，进行了复合添加钻、铜对Ｎｄ－Ｆｅ－Ｂ型磁体磁性能影响的实验。实验的合金为（Ｎｄ．Ｄｙ）－（Ｆｅ、Ｃｏ、Ｃｕ）－Ｂ，由真空感应炉熔炼，熔体用氯气雾化成...     

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.     

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).     

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.     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.     

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid(Pb)/liquid(Sn) diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field(B0.3 T). When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level(0.8–5 T), the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.     

电化学噪声数据处理方法概述

综述了常见的电化学噪声数据处理方法,介绍了直流趋势剔除、统计分析、快速傅立叶变换(FFT)法计算功率谱密度(PSD)以及小波变换处理电化学噪声信号的基本过程,并阐释了各种数学处理及所得参数的物理意义。