Method for near-net forming of a sand mold with digital flexible extrusion technology

In order to further improve the precision forming efficiency of a sand mold digital patternless casting and reduce the amount of sand mold cutting, a method for near-net forming of the sand mold with digital flexible extrusion technology was put forward. The theory, optimization algorithm and technology for sand mold nearnet forming were studied. Experimental results show that the sand mold forming efficiency can be increased by 34%, and the molding sand can be reduced by 44%. The method for near-net forming of a sand mold with digital flexible extrusion technology can effectively promote the application of digital patternless casting technology in the mass production of castings and thus greatly improves the efficiency and automation of sand mold manufacturing.

Analysis on Pore-Forming Pouring Pile Construction Technology of House Building Project

Compared with the in-place pile, the pore-forming pouring pile is more simple and convenient, with a wider range of construction. In the actual construction process, it is able to pass through complex bottom layer and water layer underground without very high requirements in equipment. The actual bearing capacity of single pile is very strong, so that it can be better to adapt to the actual needs of different scales or the different geological conditions in building. And it has been promoted and used greatly in building construction work [1]. This paper introduces the concept of the pore-forming pouring pile technology, analyzes the pore-forming construction technology and the pile construction technology, then talks about prevention problems of the pore-forming pouring pile construction in House Building Project, at last draws a conclusion that the pore-forming pouring pile technology is the most basic construction technology and is the most effective and convenient way of construction.

New Technology “Flotation to Form Agglomerates and Magnetic Separation” Allows Great Breakthrough for World Low-Grade Light Rare Earth Ores

Rare earth resources are relatively scarce worldwide, but their global consumption is increasing year-by-year. At present, China has about 36% of the global rare earth reserves, but provides 90% of the world＇s supply, which has generally met world demand and promoted the development of the world economy. In order to continuously and stably supply rare earths to international markets, the Chinese Government has financially supported the Institute of Multipurpose Utilization of Mineral Resources within the China Geological Survey to study the utilization of low-grade rare earth ores. Following many years of experimental research, the project has developed a new technology entitled ＂Flotation to Form Agglomerates and then Magnetic Separation＂, which will bring a technological revolution to the world＇s light rare earth ore dressing.

Numerical simulation on the process of multi-point forming for tube

To apply the multi-point forming technology to the field of tube processing,the process of multi-point forming for tube is studied.Numerical simulation for the process of multi-point forming for tube is achieved by using elastic-plastic FEM in ABAQUS.During simulation,reasonable coefficient of mass scaling and friction model of penalty function are used.The influence of several major technological parameters on the process is analyzed.When the tube diameter is 60 mm and the forming curvature radius is 1000 mm,the distortion rate of cross-section and the absolute forming error gradually decrease with the increasing of tube wall thickness;However,when the tube wall thickness is constant,the smaller the curvature radius,the larger the distortion rate of cross-section,but as to forming part,its absolute forming error becomes smaller.

Compact intense electron-beam accelerators based on high energy density liquid pulse forming lines

This paper provides a review of the compact intense electron-beam accelerators (IEBAs) based on liquid pulse forming lines (PFLs) that havebeen developed at the National University of Defense Technology (NUDT) in China. The history and roadmap of the compact IEBAs used todrive high-power microwave (HPM) devices at NUDT are reviewed. The properties of both de-ionized water and glycerin as energy storagemedia are presented. Research into the breakdown properties of liquid dielectrics and the desire to maximize energy storage have resulted in theinvention of several coaxial PFLs with different electromagnetic structures, which are detailed in this paper. These high energy density liquidPFLs have been used to increase the performance of IEBA subsystems, based on which the SPARK (Single Pulse Accelerator with spark gaps)and HEART (High Energy-density Accelerator with Repetitive Transformer) series of IEBAs were constructed. This paper also discusses howthese compact IEBAs have been used to drive typical HPM devices and concludes by summarizing the associated achievements and theconclusions that can be drawn from the results.

Robust Broadband Beam-Forming Based on the Feature of Underwater Target Radiated Noise

To the problem of the unknown underwater target detection, according to the feature that the underwater target radiated noise contains the stable line spectrum, a weighted method based on the main-to-side lobe ratio （MSLR） is proposed for broadband beam-forming. This weighted method can be implemented by using the following steps. Firstly, optimize the spatial spectrum of each frequency unit by the second-order cone programming （SOCP）, and obtain the optimized spatial spectrum with lower side lobe. Secondly, construct weighting factors based on the MSLR of the optimized spatial spectrums to from weight factors. Lastly, cumulate the spatial spectrum of each frequency unit via the weight statistical method of this paper. This method can restrain the disturbance of background noise, enhance the output signal-to-noise ratio （SNR）, and overcome the difficulty of traditional four-dimensional display. The theoretical analysis and simulation results both verify that this method can well enhance the spatial spectrum of line spectrum units, restrain the spatial spectrum of background noise units, and improve the performance of the broadband beam-forming.

Critical Review of Literature on Radiologic Technology Education Program Evaluation

Curriculum has achieved a varied record of success in influencing health based practices and developing professional skills. Designing and implementing an effective radiologic technology educational program curriculum requires a disciplined pedagogical approach where the instructor performs a thorough situational analysis, develops a theory based and pragmatic learning plan, and implements a course of study in accordance with the established educational guidelines and requirements. Diligent efforts are needed to enhance the relationship amongst curriculum developers and evaluators. The collection of information at the formative stage: followed by process evaluation to assess implementation as the curriculum progresses, and summative evaluation to assess impact is required for accreditation of program in the United States by the Joint Review Committee for Education in Radiologic Technology. Formative evaluation research is used to enhance effectiveness of the curriculum, guide development of teaching and learning strategies, and reveal promising and ineffective components of curriculum. This review of literature provides evidence as to what is considered to be the best practice in the program evaluation/accreditation process.

基于Deform-3D的重型汽车新型同步环精密成形过程有限元分析

重型汽车新型同步环是一种基本对称结构的、带有3个Y型凸台的环形薄壁型零件,主要用于汽车行驶中平稳快速换档。由于新型同步环形状复杂,成形困难,锻造时极易产生填充不满、折叠等情况,因此合理设计锻造工艺与模具结构是一个关键。利用非线形有限元分析软件Deform-3D对重型汽车新型同步环精密成形过程进行仿真,获得成形过程中的应变、应力、材料流动情况,同时对成形过程中的缺陷如折叠、裂纹,进行预测。通过对同步齿环成形过程分析与缺陷预测,可以有效缩短产品开发周期。

基于Free-form型锥齿轮机床的齿面制造技术

介绍了一种基于Free-form型机床切齿加工理论的点啮合齿面制造技术。提供了Free-form型机床3轴联动切齿加工基本方程及详细的计算公式。直接以工件齿轮的转角为运动参数,将机床其它各轴的运动表达为工件齿轮转角的函数。阐明了机床运动函数及其它切齿参数的确定方法。

Innovative technologies for powder metallurgy-based disk superalloys: Progress and proposal

Powder metallurgy（PM） superalloys are an important class of high temperature structural materials, key to the rotating components of aero engines. In the purview of the present challenges associated with PM superalloys, two novel approaches namely, powder preparation and the innovative spray-forming technique（for making turbine disk） are proposed and studied.Subsequently, advanced technologies like electrode-induction-melting gas atomization（EIGA）, and spark-plasma discharge spheroidization（SPDS） are introduced, for ceramic-free superalloy powders. Presently, new processing routes are sought after for preparing finer and cleaner raw powders for disk superalloys. The progress of research in spray-formed PM superalloys is first summarized in detail. The spray-formed superalloy disks specifically exhibit excellent mechanical properties. This paper reviews the recent progress in innovative technologies for PM superalloys, with an emphasis on new ideas and approaches, central to the innovation driving techniques like powder processing and spray forming.

Lightweight in Automotive Components by Forming Technology

Lightweight design is one of the current key drivers to reduce the energy consumption of vehicles.Design methodologies for lightweight components,strategies utilizing materials with favorable specific properties and hybrid materials are used to increase the performance of parts for automotive applications.In this paper,various forming processes to produce light parts are described.Material lightweight design is discussed,covering the manufacturing processes to produce hybrid components like fiber-metal,polymer-metal and metal-metal composites,which can be used in subsequent deep drawing or combined forming processes.Approaches to increasing the specific strength and stiffness with thermomechanical forming processes as well as the in situ control of the microstructure of such components are presented.Structure lightweight design discusses possibilities to plastically form high-strength or high-performance materials like magnesium or titanium in sheet,profile and tube forming operations.To join those materials and/or dissimilar materials,new joining by forming technologies are shown.To economically produce lightweight parts with gears or functional elements,incremental sheet-bulk metal forming is pre-sented.As an important part property,the damage evolution during the forming operations will be discussed to enable even lighter parts through a more reliable design.New methods for predicting and tailoring the mechanical properties like strength and residual stresses will be shown.The possibilities of system lightweight design with forming technologies are presented.A combination of additive manufacturing and forming to produce highly complex parts with integrated functions will be shown.The integration of functions by a hot extrusion process for the manufacturing of shape memory alloys is presented.An in-depth understanding of the newly developed processes,methodologies and effects allows for a more accurate dimen-sioning of components.This facilitates a reduction in the total mass and an increasing performance of vehicle components.

Effects of Processing Technologies on Mechanical Properties of SiC Particulate Reinforced Magnesium Matrix Composites

Mg matrix composites with SiC particles ranging from 5vol%-25vol% were prepared using stirring casting method. Die casting, squeezing casting, and extrusion were applied for inhibiting or eliminating the defects such as gas porosity and shrinkage void. Through die casting and squeezing casting, most of the defects in Mg matrix composites could be eliminated, but the mechanical properties were improved limitedly. On the other hand, after hot extrusion, not only most of the defects of as-cast composites ingots were eliminated, but also the mechanical properties were improved markedly. With the addition of SiC, the tensile strength, yield strength and elastic modulus of as extrusion SiCp/AZ61 composites increased remarkably, and the elongation decreased obviously.

Web Form间数据交互的应用研究

文章系统研究了WebForm间的数据交互技术,提出了“类方法”、“POST/GET方法”、“Cookie方法”、“隐藏域方法”、“Context方法”、“Session方法”、“Application方法”。

寿命与成形性能的完美结合——PrintForm HR成形网

介绍了福伊特造纸织物最新开发的新产品——PrintForm HR成形网,重点论述了这一产品的经线/纬线组合、纬线结构,以及使用效果。这种成形网采用SSB技术和8梭口反面结构,与常规结构相比,可以延长成形网的使用寿命、提高脱水能力并增强横向挺度。对于采用高填料含量且纸页质量和留着率要求较高的纸机,这种耐用的成形网效果明显。

中国塑性成形技术和装备30年的重大突破与进展

1994以来的30年,在国家重大需求的强劲牵引下,我国塑性成形技术与装备取得举世瞩目的巨大成就,研制出一大批世界第一的成形装备,实现了三大技术跨越,形成了规模最大的研究队伍,我国塑性成形技术总体水平进入世界先进国家行列,多个单项技术和装备达到国际领先水平。选择了其中8项最具代表性成果,并介绍其在塑性工程理论和技术上取得的重大突破以及对国家重大装备研制的突出贡献,分析了我国塑性成形技术与国际领先水平的差距。最后对我国塑性成形技术发展将呈现出的“三超两高”五大发展趋势进行了展望。

A Compliance Society: Social Form and Legal Form of Future

Algorithm-based technologies are promoting the arrival of legal singularity-a time node when the transformation of legal form happens.Frontier researches have demonstrated that artificial intelligence and big data technology will drive the reform of legal system.This article puts forward a new academic model“the compliance society”,which can be defined as a society where all legal subjects abide by the law proactively.The concept is a novel vision of the society of future based on the maximum utilization of modern legal technology.We first explore the feasibility of constructing a compliance society,and then use cost-benefit analysis to assess the possible socio-economic effects.

A Brief of the Technological Beauty Effect on Modem Interior Design

As a practical art, interior design is related to the technological beauty closely. Technological beauty is the combination of technology and art, there will be important meaning by researching materials,function, and forms of beauty in interior design and green interior design.

齿轮精密塑性成形理论技术装备研究与应用

齿轮是传动系统的核心基础件,被广泛应用于机械、汽车、航空航天装备等领域。齿轮传统制造技术为切削加工,其材料利用率低、加工周期长,特别是金属流线切断,损害齿轮性能,无法满足高端装备发展需求。齿轮精密塑性成形制造技术具有节能、节材、高效和优质等特点,是高性能齿轮技术发展方向。阐述了齿轮精密塑性成形理论方法,分析了国内外圆锥直齿轮、圆柱直齿轮和圆柱螺旋/斜齿轮精密成形技术特点;介绍了齿轮精密成形典型装备及产线,总结了齿轮无切削摆辗精密成形和锻造精密成形应用情况。此外,展示了圆锥螺旋齿轮多自由度包络成形和非圆齿轮锻造成形新方法,为高性能齿轮无切削成形制造技术装备研究与应用提供了参考。

基于AutoForm前门框上边梁内板热成形仿真试验

基于AutoForm R6软件,以某汽车前门框上边梁内板为例,阐述了热成形工艺方案及模拟分析方法,总结了热成形过程中的问题及处理办法,并研究了保压压力对冷却速率的影响规律。

钻爆法公路隧道防排水技术发展综述

为研究钻爆法公路隧道防排水技术的发展趋势和未来方向,系统梳理了防排水技术的发展历程、技术要求、设计施工和维护技术等内容,并对需要关注的问题及下一步发展方向进行展望。结果表明:按照隧道建设的技术发展水平,防排水技术可划分为圬工时代和后混凝土时代,已实现原则指导、设计优化、材料革新、施工控制、标准保障及运营维护的基本构架;中国在新修订的规范中增补了隧道渗漏水量化标准,使防水等级规定更具客观性、科学性;从防排水系统构造形式的对比情况看,控制排水型隧道能兼顾隧道衬砌水压力和维护隧道区生态平衡等多方面需求;钻爆法隧道防排水技术虽然增加了一些可维护性设计,但仍以功能性设计为主,且现有技术难以满足防排水系统的维护需求。应当注意:防排水技术是一个系统性问题,需要建立基于全寿命周期的建管养一体化防排水体系,并对防排水系统选型和控制型防排水技术进行系统性研究,通过对全寿命周期内隧道排水的环境影响进行分析评价,确定合理的防排水构造型式;另外,需加强防排水系统优化及新工艺研究,加快新型防排水材料的开发;同时要加强维护技术研究,尤其是可维护性技术和修复性技术研究。