The thermal performance Rov of Flat-Plate Closed-Loop Pulsating Heat Pipe(FCLPHP) are effected by several elements such as the heat load Q, the tilt angle θ and the filling ratio F, they are interacted each other.In order to predict the effect of Q and θ on the thermal performance at locations Q and θ other than the experimental data conditions, and to study the relationship among the Rov, Q and θ in the range of the experimental data, we need a fitted regression model to estimate the function relationship that describes the data.The postulated depends on the range of the regression variables encountered in the data.In this paper, a simple model was developed.Since the coefficients in the model have been estimated from the experimental data, studies were carried out on an experimental set-up.FC72 was employed as working fluid.Method of least squares was used for building the model.By using the model, effects of the beat load and the tilt angle on the thermal performance of FCLPHP were discussed.It was found that the tilt angle had minimum value in a certain heat load in the experimental range (θ=30°-70°), and it increases with the increase of heat load.A sensitivity analysis was done with the model.

关键词：钢铁；脉动热管；热性能；整体热阻

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This project addressed the goal of National Strategy for Surface Transportation Research to improve highway structures by enhanced materials, in particular by design and implementation of new, drastically improved steels with respect to strength, low-temperature fracture toughness, weldability, and weatherability. The goal of the project was to develop, standardize and commercialize a family of low-cost, high-performance steels for infrastructure applications. As a result we developed steels with yield strength of 50 to 80 ksi, with Charpy absorbed fracture energy significantly exceeding requirements of bridge construction codes at temperatures down to -100DGF, steels that are easy to weld without pre-heat or post-heat, steels that exhibit best weathering performance among other commercially available steels. In addition these steels are easy to produce; production does not involve any heat treatment or thermo-mechanically controlled processing which is available only to several US Steel companies. The steels developed in this project were commercially produced in the form of plate and wide-flange I-beams. The steels were used for seismic retrofitting of one bridge (in 2000) and for construction of two new bridges (in 2006 and 2010).

关键词：钢材；成本；营销；桥梁；建筑

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Fracture toughness and fatigue properties of pipeline steels play a critical role in developing advanced high-pressure hydrogen infrastructure for alternative fuel pipelines program. The reliability of structure components, particularly resistance to damage and failure in the intended service environment, is highly dependent on the selected materials. An effective surveillance program is also necessary to monitor the material degradation during the course of service. Steels have been proven to be desirable for hydrogen infrastructure. However, hydrogen embrittlement is an important factor that limits steel performance under high-pressure hydrogen conditions. In order to reach the above goal, we have proposed an innovative technology, based on spiral notch torsion test (SNTT) methodology, to effectively investigate the material performance of X52 pipeline steel. The SNTT approach was successfully demonstrated and extended to X52 steels during the performance period. In addition to single notch front geometry, the crack growth behavior of the SNTT process has been effectively established using an integrated experimental, numerical and analytical approach. The results indicate that the proposed protocol not only provides significant advance in understanding the compliance evolution of the SNTT specimen, but also can be readily utilized to assist future development of hydrogen infrastructures. In FY2011, an extensive study was performed to characterize the fracture toughness degradation of AISI 4340 high-strength steel exposed to high-pressure hydrogen using in situ spiral notch torsion tests. This effort included equipment setup and calibration, sample design and fabrication, finite element simulation of the specimen fracture, and fractographic characterization using advanced microscopic techniques. The detailed description of the results is summarized in by Wang (Wang 2011).

关键词：管道；钢；断裂强度；缺口冲击试验

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Severe localized corrosion of a 316 stainless steel autoclave occurred during investigating Type H Portland cement stability in 0.16 M CaCl(sub 2) + 0.02 M MgCl(sub 2) + 0.82 M NaCl brine in contact with supercritical CO(sub 2) containing 4O(sub 2). The system operated at 85 C and pressure of 29 MPa. However, no corrosion was observed in the same type of autoclave being exposed to the same environment, containing Type H Portland cement cylindrical samples, also operating at pressure of 29 MPa but at 50 C. The operation time for the 85 C autoclave was 53 days (1272 hours) while that for the 50 C autoclave was 66 days (1584 hours). Debris were collected from the base of both autoclaves and analyzed by X-ray diffraction (XRD). Corrosion products were only found in the debris from the 85 C autoclave. The cement samples were analyzed before and after the exposure by X-ray florescence (XRF) methods. Optical microscopy was used to estimate an extent of the 316 stainless steel corrosion degradation.

关键词：腐蚀;不锈钢;高压蒸汽灭菌器;盐水

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The construction industry has historically made use of four materials: stone, timber, concrete, and steel. In recent years, civil engineers have been seeking alternative materials to steel and concrete that may be less vulnerable to environmental damage. Rising public concern about traffic delays experienced during construction have increasingly influenced civil engineers to seek materials and methods that allow more rapid construction. At the same time, costs must be competitive with traditional materials because of reduced public sector resources to maintain transportation infrastructure. Fiber-reinforced polymer (FRP) composites have emerged as an attractive potential alternative. Inspections of sign structures by the Florida Department of Transportation (FDOT) have revealed the occurrence of premature corrosion of galvanized steel structural members. As a result, FDOT engineers are also seeking alternative materials that may be employed in these structures.

关键词：建筑材料；石材；木材；混凝土；钢材

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In this paper we discuss the standard Jominy curve method, which is used for hardness and microstructure prediction at the core of steel parts of different shapes. It is shown that the simplified method of calculation needs verification by an exact analytical solution of the problem connected with the Jominy end-quench method. For this purpose, an exact analytical method of calculations is proposed. It is established that the cooling rate at the core of steel parts can differ by up to 12as compared with the self-regulated boiling process and extremely forced convection.

关键词：钢铁；显微组织；硬度；顶端淬火曲线；冷却速率

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Laser Shot Peening without protective Coating (LPPC) was performed on SS304 austenitic stainless steel using a 300 mJ, 10 ns pulse, 1064 nm wavelength Nd:YAG laser with three different pulse densities. A thin layer of water was used as a confinement layer. The peened specimen was characterised with XRD, AFM and a Profilometer. The stress evaluated at the surface of the laser peened sample shows a maximum compressive stress of 1.6 GPa. The surface roughness and depth profile of microhardness before and after LPPC were investigated.The LPPC region indicate substantial improvement in microhardness and compressive residual stress, with marginal increase of surface roughness.

关键词：钢铁；激光冲击强化；脉冲密度；局限层

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Diamond-coated drawing dies are considered as ideal drawing dies for their unique characteristics, such as high hardness, wear resistance and low friction. In order to utilize the superior characteristics of diamond coatings towards improving the drawing performance, the nonlinear FEM simulation is used to simulate the whole low carbon steel tube hollow sinking process, with 2D axi-symmetric elastic-plastic element. Based on the simulation results, the distributions of the axial stress and radial stress are analyzed, the influence of parameters of drawing dies on the diameter shrinkage is investigated. Optimal die parameters are obtained.

关键词：钢铁；金刚石冲模；有限元模拟

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To enhance plate quality of cold rolling strip steel, a method based on Ant Colony Optimization with Quantum Action (ACO-QA) is developed. In this method, each ant position is represented by a group of quantum bits, and a new quantum rotation gates are designed to update the position of the ant. In order to makes full efficiency, a pretreatment using fuzzy method is firstly adapted before resolving the mathematical model with ACO-QA. This method overcomes the shortcoming of ACO, which is easy to fall into local optimums and has a slow convergence rate in continuous space.

关键词：钢铁；缺陷识别；冷轧；量子算法；蚁群优化算法

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关键词：钢铁;射流冲击冷却;膜状沸腾；CFD；VOF；热传系数

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