采用CO2气体保护药芯焊丝电弧焊,研究了15CrMoR钢碱性渣系药芯焊丝的焊接工艺性,及焊接接头的组织和性能.结果 表明,焊接过程中飞溅较大,焊后焊缝成形良好,焊接接头中焊缝和热影响区的微观组织为贝氏体,与酸性渣系药芯焊丝的焊接接头相比冲击吸收能量有明显提高,各项性能满足母材要求.

为了准确高效计算马鞍形焊接接头焊材消耗定额,提出了一种基于逆向思维的求解方法,通过三维建模获取多种规格的马鞍形焊接接头体积,运用拟合方式获得单位长度焊缝的体积V与支管壁厚t、系数γ的函数关系,最终得出计算马鞍形焊接接头焊材消耗定额公式.

G115钢是研发630℃高效超超临界锅炉关键部件的重要候选材料之一,通过斜Y形坡口焊接裂纹试验、焊接热影响区最高硬度试验,对G115钢焊接冷裂纹敏感性进行研究.结果表明:G115钢冷裂倾向较大,但是预热到150℃时,可有效降低焊接冷裂纹出现的概率.

某换热器项目短筒身选用12Cr2Mo1VR材质,管板选用20MnMoNb锻件材质.12Cr2Mo1VR和20MnMoNb在力学性能和化学成分上差异较大,生产难度较大.针对异种钢焊接,选择了合适的焊接材料,制定了合理可行的工艺,保证了产品的焊接质量.

Compare with the two-dimensional (2D) structure of graphene, introducing three-dimensionality to graphene can provide more molecular adsorption sites by fully using the three-dimensional volume of laser. Here, we describe the fabrication of 3D wrinkled Ag NPs-graphene hybrid film which rarely contains two classes of wrinkles, micro wrinkles and nano wrinkles. We obtain a new 3D wrinkled Ag NPs-graphene hybrid structure by the buckling and crumpling of graphene to produce nano wrinkles with the formation of the micro wrinkles of the polystyrene (PS) polymer. We also have carefully examined evolution of crumpling and optimized the size and spacing of deposited Ag NPs on graphene for higher SERS intensity. The 3D Ag NPs-graphene hybrid film shows at least 1 order of magnitude lower detection limit than that of the flat one by SERS detection of triphenyl phosphine (PPh3). We believe that this wrinkled Ag NPs-graphene hybrid structure could be applied as a great potential platform for highly sensitive SERS substrate.

The radiation induced transmittance change of the lens with antireflection films of MgF2/ZrO2/Al2O3 on both surfaces was investigated under the 60–1000 keV electron and/or proton radiation on a space complex radiation simulator. The results show that the transmittance of lens is monotonously decreased with increasing radiation fluence. The major absorption band around 430 nm is caused by F2 center, F+ center and VŌH center in the antireflection films. The weak absorption band in 500–800 nm is related to the hole-type color center and the impurity-type color center under higher radiation fluence. Under the proton energy <100 keV, the radiation induced damage of antireflection films dominates the variation of transmittance, which is increased with increasing radiation energy. When the energy exceeds 100 keV, the energy loss in films is reduced and the substrate coloring becomes the main cause for the transmittance change. Under electron radiation, the change of transmittance increases with increasing energy while the energy loss in films dramatically decreases with increasing electron energy. In this case, the radiation induced effect on substrate is a dominant factor. The coloration of films also has certain contribution to transmittance change due to the scattering effect of electrons. In the near-Earth space, electron fluxes are higher than proton ones and the fluxes of low-energy charged particles are higher than high-energy charged particles. Therefore, for evaluation of radiation effects on the optical elements with films, the low-energy electron exposures are preferred, with the low-energy proton exposures being the second option.

Evolution and mechanism of the induced loss of the 1310 nm working-wavelength "Panda" type quartz PM fiber irradiated by the 1 MeV and 170 keV electrons respectively were experimentally investigated using electron accelerator. The results show that, fiber loss exhibits an exponential increase with increasing radiation fluence, which is higher under low-energy electrons than under high-energy electrons. The irradiated quartz fibers show an annealing effect. The restored loss of the fiber irradiated by high-energy electron is higher than that by low-energy electron. The radiation induced loss of quartz fiber has two mechanisms of Si-OH absorption and H-2 absorption. Under lower electron energy, the energy deposition of fiber core is in majority leading to more radiation defects forming while the loss is mainly controlled by Si-OH. In the case of the fiber subjected to high-energy electron radiation, the absorbed dose of fiber core is relatively low, which is dominated by H-2 absorption. Hydrogen that is involved in both mechanisms is generated by radiation induced degradation of polymer coating and diffuses into fiber core.

•Silver nanoparticles were deposited on the monolayer graphene and spin coated with PMMA, forming a PMMA/Ag NPs/graphene substrate.•The silver nanoparticles were uniformly distributed on the graphene.•The hot spots adhered backside to the graphene makes the exposed graphene a hot surface.•The SERS substrate showed highly repeatable and sensitive SERS performance.•The graphene-enhanced SERS substrate showed a great potential in detection of pesticide residues in environmental water.

为了研究堆焊单一E309L熔敷金属的焊接工艺和接头性能,采用埋弧焊(SAW)在14Crl MoR基体上堆焊一层EQ309L焊带,焊接过程中严格控制焊接热输入和采用有效的消应力退火热处理制度,保证堆焊层顺利通过无损检测以及弯曲、化学、铁素体数量、硬度试验、金相组织分析和晶间腐蚀等理化性能检测.结果表明,采用埋弧焊(SAW)堆焊单层EQ309L时堆焊层的塑韧性能满足要求,晶间腐蚀试验合格,可以用在压力容器的表面堆焊中.

为了研究堆焊单一E309L M o T1-4熔敷金属的焊接工艺和接头性能,采用药芯焊丝气体保护焊(F C A W)在14C r1M o R基体上堆焊双层E309L M o T1-4焊丝,焊接过程中严格控制焊接热输入和采用有效的消应力退火热处理制度,保证堆焊层顺利通过无损检测、无损检测、力学性能和金相组织分析等理化性能检测.试验结果表明:采用药芯焊丝气体保护焊(F C A W)堆焊双层E309L M o T1-4焊丝时堆焊层的塑韧性能满足要求,但铁素体数量超过12,适合用在对耐蚀性要求不高的容器产品中.

Under conditions of high temperature and pressure,in order to prevent corrosion medium corro-sion of the equipment inside wall,the inner wall of a lot of equipment to be cladding 347 type stainless steel overlay,such as the hydrogenation reactor,converting furnace and so on.However,overlay materials rely heavily on imports.The surfacing technology was compared by using domestic and imported 347 type stainless steel flux-cored wire.The results showed that:domestic flux-cored wire surfacing technology adaptability is narrow;By adjusting some domestic flux-cored wire welding parameters,the surfacing lay-er performance is improved to meet the requirements of product.

In this paper, compressive behavior of electrodeposited nano-crystalline (nc) Ni at various temperatures and strain rates is studied using a low temperature mechanic test system. Plastic deformation mechanisms of nc Ni caused by compression are characterized by the strain rate sensitivity index, the activation volume, and examined by scanning electron microscopy and high resolution transmission electron microscopic analysis. Results show that at low temperatures, the plastic deformation of nc Ni is mainly dominated by grain boundary accommodated dislocations. In other words, during plastic deformation of nc Ni at low temperatures, the intrinsic dislocation at the grain boundary bends up and expands without obstacles to the opposite grain boundary in the inner grain dislocation-free zone, until the occurrence of similar cutting forest-dislocation behavior appearing at opposite grain boundary. Moreover, the residual dislocations in the grain boundary bending out during plastic deformation could increase the strain compatibility and decrease the stress concentration. At room temperature, the plastic deformation mechanism of nc Ni is controlled by the deformation of grain boundary accommodated dislocations and grain slipping/rotating. Based on the above analyses, differences in compressive behavior of nc Ni at various temperatures and strain rates can be revealed by the correlation of deformation mechanisms of grain boundary accommodated dislocations and residual dislocation movement, temperature and defects in nc Ni.

We presented a way to control the output of the nematic liquid crystal (NLC) random laser with a response time of hundreds of milliseconds by a continuous-wave laser beam with the power of several milliwatts. The lasing intensity can be tuned continuously by variation of the control power in the range from 0 to 5 mW or the lasing output can be switched on and off by turning off and on the control beam when the control power reaches 6 mW. The control power-dependent lasing polarisation and the self-phase modulation of the control beam indicate that the photothermal effect, which leads to the change of the order of the NLC and subsequently the change of the long-range fluctuation of the dielectric tensor, is mainly responsible for the controllability of the random lasing.

概述了SA-213T23管材在电站锅炉中的应用情况.分析了SA-213T23小口径管的化学成分及力学性能,以解决实际生产中SA-213T23小口径管焊后热处理时间较长的问题为目的,通过对焊材厂家产品调研,采用英国METRODE公司和德国蒂森焊接技术有限公司研制的焊材进行施焊.通过改变热处理时间对热处理工艺试验进行探索.以ASME标准要求的合格准则对比分析焊接接头性能,为缩短SA-213T23管材热处理保温时间、简化热处理工艺提供了依据.

针对锅炉、压力容器焊接工艺评定用ASMEⅨ和EN ISO 15614-1标准的差异和特点进行了对比分析。通过对这些标准适用范围、焊接试件、检测项目和焊接工艺评定的代用范围等方面的分析,认为:ASMEⅨ适用范围更广,焊接工艺评定的认可范围较大,而EN ISO 15614-1要求的检测项目更多、焊接工艺评定的认可范围相对较窄。目前,国内的锅炉、压力容器制造企业更加熟悉ASME标准,但随着欧洲业务的不断拓展,对EN ISO 15614-1标准的理解和掌握就变得越来越重要。

In this paper, compression test is carried on electrodeposited nano-crystalline (NC) Ni at 77 K. The results show that the NC Ni has extremely high compressive strengths: around 2.5 GPa at room temperature (RT), 3.5 GPa at 77 K, and moderate plasticity with 0.1 fracture strain at RT, 0.05 at 77 K. The strain rate sensitivity m and activation volume v are calculated, and scanning election microscope and high-resolution transmission election microscope are used to verify the deformation mechanism. Analysis indicates that the dislocation interaction with grain boundary (GB) dominates the deformation of NC Ni both at 77 K and RT. Based on the calculated values of m and v, the deformation process is described by considering the intrinsic dislocation of GB bowing out and expanding towards opposite GB in the inner grain dislocation-free zone. And the mechanism is studied in the residual dislocation parts affecting the increase of strain compatibility and the decrease of stress concentration. It is indicated that the difference in compression property between at RT and 77 K is relatated to grain boundary-dislocation coordination mechanism and relation between residual dislocation motion and temperature.

A high-energy proton irradiation test was conducted on the electro-deposited nano Ni and the common coarse-grained Ni with different incident angles. The energy loss of the proton penetrating through the nano Ni was investigated. Results show that, high-energy protons exhibit higher residual energy after penetrating the nano Ni than those penetrating the coarse-grained Ni under the same sample thickness and irradiation condition. The high-energy protons lose less energy in grain boundaries during irradiation. The large amount of grain boundaries in nano Ni decreases the energy loss of the proton interacting with the test materials.

We report on a theoretical investigation of the coupling between magnetic plasmons (MPs) and Tamm plasmons (TPs) in a metal-dielectric Bragg reflector (DBR) containing a gold nanowire pair array embedded in the low refractive index layer closest to the metal film. Strong coupling between MPs and TPs is observed, manifested by large anticrossings in the dispersion diagram. It creates a narrow-band hybridized MP mode with a Rabi-type splitting as large as 290 meV. Upon the excitation of this hybridized MP mode, a 2.5-fold enhancement of the magnetic field in the center of nanowire pairs is achieved as compared with the pure MP of the nanowire pairs embedded in a bare DBR structure (without the metal film). This result holds a promising potential application in magnetic nonlinearity and sensors.

In this work, the microstructure and optical properties of the Mo/Si multilayers mirror for the space extreme-ultraviolet solar telescope before and after 100 keV proton irradiation have been investigated. EUV/soft X-ray reflectometer (EXRR) results showed that, after proton irradiation, the reflectivity of the Mo/Si multilayer decreased from 12.20% to 8.34% and the center wavelength revealed red shift of 0.38 nm, as compared with those before proton irradiation. High-resolution transmission electron microscopy (HRTEM) observations revealed the presence of MoSi2, Mo3Si and Mo5Si3 in Mo-on-Si interlayers before irradiation. The preferred orientation such as MoSi2 with (101) texture and Mo5Si3 with (310) texture was formed in Mo-on-Si interlayers after proton irradiation, which led to the increase of thickness in the interlayers. It is suggested that the changes of microstructures in Mo/Si multilayers under proton irradiation could cause optical properties degradation.

The chemical composition of SA-213T91 and SA-387Gr91CL2 and the difficulties in the welding of the membrane wall tube panel produced by T91 steel are analyzed. The similar materials to the actual product are tested according to the relevant technical standards. The result shows that the selected welding consumables can meet the requirements of welding performance, and the size of the weld can meet the requirements of the relevant technical standards. By the comparison of the differences between test and product, the methods to control the preheat temperature and some points in production are proposed.