新型气压焊轨机参数采集与质量管理信息系统

根据钢轨现场气压焊接质量要求和作业工况条件,利用VB技术开发了新型气压焊轨机参数采集系统,对钢轨气压焊焊接过程参数进行实时采集,通过专门设计的数据处理软件进行数据处理分析,获得气压焊过程相关参数的曲线,并生成质量信息报表,为追溯现场钢轨焊接工况、诊断焊轨质量和实现焊轨工程质量现代化管理提供依据.     

钢轨现场焊接参数远程采集系统

目前我国铁路换铺维修工程的钢轨现场焊接主要由焊轨车完成,其施工作业点自然环境条件复杂。为了实时获取焊接数据,跟踪钢轨现场焊接质量,设计了由数据整合工具软件、物联网网关设备和云平台组成,能通过移动网络将钢轨现场焊接参数实时上传至云平台的钢轨现场焊接参数远程采集系统,以供焊接技术管理人员共享,从而实现焊接参数的远程采集分析与质量评估。该系统成功应用于YHGQ-1200型气压焊轨车的现场施工。     

GPW-1200型气压焊轨机控制系统研制

目前国内各铁路局进行钢轨换铺时广泛使用的GPW-1200型气压焊轨机以PLC及相应模块为控制核心,具有燃气柔性控制、加热器柔性摆动、油压控制、焊接过程控制、冷却过程控制、正火过程控制等控制功能。GPW-1200型气压焊轨机控制系统按照高铁钢轨气压焊焊接要求,实现了气压焊轨机的控制,避免了人为因素的影响。现场应用表明,该控制系统能够适应钢轨现场线下焊、线上焊和焊复等工况,钢轨焊接质量优良、稳定。     

国内钢轨焊接的现状及发展趋势

钢轨焊接技术对无缝线路的发展具有重要影响.尽管针对钢轨焊接的闪光焊、气压焊、铝热焊及电弧焊等新工艺不断出现,但因囿于上述4种焊接方法的热源特性及焊接工艺特点,使得钢轨焊接接头性能与质量的改善及焊接效率的提高都非常有限.为此,提出了将电子束焊应用于钢轨焊接的思路,并进行了U71Mn钢轨的电子束焊初步试验.结果表明电子束焊...     

钢轨焊接接头冲击吸收功统计与分析

统计与分析了U71Mn和U75V系列钢轨接头的室温冲击吸收功性能及规律,系统全面地了解了钢轨焊接接头冲击性能特点,可为焊接工艺制订规范和质量控制提供参考依据。统计与分析结果表明:铝热焊、移动焊、固定焊和气压焊接头冲击吸收功的平均值分别为4,14.1,13.8,14.1 J,铝热焊接头的韧性最差,闪光焊和气压焊相当;不同焊接方法不同系列钢轨(除气压焊外)的冲击吸收功平均值轨头轨底轨腰;气压焊接头冲击吸收功平均值轨底轨头轨腰;轨腰由于脆性夹杂物、疏松、偏析等缺陷原因冲击吸收功最低。U71Mn和U75V系列钢轨焊接接头全断面各部位的冲击吸收功变化规律相似,距离钢轨断面对称中心线越近,冲击吸收功越低。     

钢轨气压焊加热器回火现象分析及防治措施

气压焊是钢轨现场焊接的主要方法之一,回火是气压焊氧乙炔混合气体燃烧特有的现象,避免回火现象对提高钢轨焊接质量和效率有很大影响。在详细分析了钢轨气压焊加热器回火现象产生的原因和危害后,根据现场的实际情况,提出了防治回火的具体措施。     

钢轨气压焊接头的超声相控阵检测技术研究

常规超声脉冲反射法检测钢轨气压焊接头时,需要更换不同K值探头检测钢轨气压焊接头的不同区域,探伤过程耗时长,效率低。超声相控阵技术可以灵活调节扫描角度,能有效提高检测效率。主要采用超声相控阵方法对钢轨气压焊焊缝进行探伤效果分析研究,实验中采用CTS-602型相控阵仪器、含机械加工缺陷的钢轨气压焊焊缝试样,通过确定合理的实验参数和检测方案,进行超声相控阵探伤检测。实验结果表明超声相控阵对气压焊接头检测效果好,检测效率高。     

钢轨焊接技术及质量控制

综述3种钢轨焊接方法闪光焊、气压焊和铝热焊的原理及存在问题,并提出提高我国钢轨焊接质量的建议。     

基于AMESim软件的钢轨气压焊顶锻系统仿真

随着高速铁路的快速发展,对钢轨接头的要求也越来越高.气压焊适用于无缝线路的单元焊和锁定焊.其中顶锻过程是影响焊接质量的重要因素,研究影响顶锻过程的因素有利于改善焊接质量.采用AMESim仿真软件搭建项锻系统模型,根据气压焊的工艺要求设置子模型的各项参数,分析在顶锻过程中活塞杆的运动情况,得出溢流阀自身的特性直接影响顶锻...     

客运专线钢轨焊接技术

我国铁路钢轨焊接主要采用铝热焊、气压焊和闪光焊。综述了客运专线所涉及的这三种钢轨焊接方法的特点、工艺及设备以及常见缺陷产生原因和相应对策，并提出了提高我国钢轨焊接质量的建议。     

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.     

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.     

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).     

Structural Optimization of Electromagnetic Swirling Flow in Nozzle of Slab Continuous Casting

During the slab continuous casting process, the flow field of molten steel in the mold plays a decisive role in the quality of the slab. In this paper, electromagnetic swirling flow in nozzle technology is proposed to control the flow field in mold.This technology can drive molten steel to rotate inside the submerged entry nozzle by electromagnetic force, thereby controlling the flow field. This research shows that it can reduce the impact of molten steel on the bottom of nozzle and partly reduce the negative pressure at the upper part of nozzle outlet which is even eliminated by optimizing the structure and angle of nozzle. The area of heat flux of the mold wall becomes larger, and the crest value of heat flux gets lower than that without swirling in nozzle and any nozzle optimization. The meniscus fluctuates smoothly, and the flow velocity at the top surface is within a reasonable range. The temperature field distribution in the mold is uniform which was beneficial to the growth of equiaxed crystal and decreased element segregation.