气力输送在我厂铸造车间的应用

气力输送在铸造车间砂处理工部的使用，已极其广泛，如何充分发挥气力输送在铸造厂（车间）的作用，本文认为气力输送设备的设计，制造工作已有成熟的专业生产厂家设计、制造，产品的质量和性能均达到用户要求，而气力输送设备的使用、维护工作对于众多厂家来说，要有一个适应、熟悉、掌握的过程，只有了解掌握气力输送，才能更好的用于铸造生产，减轻劳动强度，改善生产环境．     

玻璃钢贮槽的使用总结

本文针对整体玻璃钢贮槽使用中出现的种种破坏现象，分析产生破坏的原因，采取修补的措施，提出如何正确选用玻璃钢贮槽。     

铸造工厂的混砂机使用

分析了铸造车间混砂机的使用情况，指出在合理混制工艺下，减少混砂机出现故障，主要是控制混砂量，防止机械过载。     

安装交流接触器应注意的问题

交流接触器用途广泛，其使用寿命的长短，不仅取决于产品本身的技术性能，而且与产品的正确安装使用是否符合要求有关，下面就安装交流接触器应注意的问题，提出自己的几点看法。一．安装前的检查1，应检查产品的铭牌及线圈上的技术数据（如额定电压、电流、操作频率和通电持续率等）是否符合实际使用要求。2．用于分合接触器的活动部分，要求产品动作灵活无卡住现象。3．将铁芯极面上的防锈油擦净，以免油垢粘滞而造成接触器断电不释放。这点需切记，很多维修电工往往忽视了这最重要的一点。4．检查与调整触点的工作参数（开距、超程、初压…     

宁波康强电子：坚持技术创新 电镀废水循环使用实现清洁生产

电镀废水对环境影响很大，如何做到“增产不能增加废水排放”，成了宁波康强电子股份有限公司的最大问题。为此，公司投入大量资金进行环保创新：（1）从源头减少电镀产生的清洗水混入电镀液，电镀液实行全封闭循环使用；（2）对清洗废水实行分类处理，综合利用，减少废水排放；（3）对排放废水进行二级处理，回收中水用于净水制取，重新投用到电镀线，同时回收固体废渣提取银、镍、铜。该项目在2005年底试验成功，2006年节水和减少排放效果显著：全年节约用水35．3万t，万元产值水耗降低45．17％，而且实现了销售收入增加57．5％的良好业绩，受到上级领导和有关部门的表彰。     

金刚石排锯及其合理使用

本文分析总结了锯切加工大理石、花岗石、毛板的金刚石排锯条的安装，使用原则，研究了金刚石刀头的配方，结构等质量性能。     

焊接与切割设备的使用与维修(三)——电弧焊机的使用须知和交流弧焊机的安装

讲述了电焊机使用中应注意的事项，介绍了交流焊机的特点和弧焊变压器的分类。从交流弧焊机的安装地点及环境，动力线、开关、熔断器和焊接电缆的选择等方面详棕了焊机的正确安装是保证焊机正常使用、保证安全及节约能源的重要条件。     

我国井下铲运机使用与维修存在的问题与对策研究

在广泛调查、收集和整理国内井下矿山铲运机使用与维护技术资料的基础上，综述了我国主要井下矿山的使用和维护概况，并指出了所存在的问题及分析了所存在问题的原因，同时提出了今后我国使用与维护铲运机的措施。     

点焊机的使用与维修

点焊机的使用与维修空军第一航空学院［信阳］（４６４０００）郭必新，李建霞Ｏｐｅｒａｔｉｏｎａｎｄｍａｉｎｔｅｎａｎｃｅｏｆｓｐｏｔｗｅｌｄｉｎｇｍａｃｈｉｎｅｓ￥（ＡｒｃｆｏｒｃｅＮ０１ａｅｒｏｎａｕｔｉｃａｌｌｎｓｔｉｔｕｔｅ）ＧｕｏＢｉｘｉｎｅｔ...     

经济型数控车床中机械坐标系与系统坐标系的关系及影响

在使用数控车床进行零件加工时，经常要涉及到两个坐标系，一个是机械坐标系，一个是系统坐标系。而对很多初学者来说，由于对坐标系的理解、坐标系之间的关系、坐标系的平移缺乏清晰的认识，给他们的学习及使用造成了不少麻烦。对于数控车床的使用，坐标系的问题是关键的问题，是正确进行零件加工，保证工艺要求的基础。为了更加形象地进行分析说明，现以GSK－928CNC控制系统为例进行说明。一、数控车床上的坐标系数控车床上的坐标系一般包括机械坐标系和系统坐标系，两者之间除了自身独有的特点外，也有很多内在的关系。1．机械坐标系…     

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.     

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.     

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.     

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.