火焰法在硬质合金上合成金刚石薄膜

用Ｏ２／Ｃ２Ｈ２燃烧火焰法在各种不同性质的衬底材料上直接合成金刚石薄膜，研究了硬质合金刀头的不同的冷却方式下，对合成金刚石膜的影响。结果表明：ＹＧ６硬质合金由于Ｃｏ的存在影响了金刚石膜的质量；当冷却方法不当时，硬质合金头刃部易过热；采和分段沉积法可改善金刚石膜与硬质合金的附着性。     

硬质合金YG8上金刚石薄膜的成核研究

利用调节基底表面碳流量的方法促进了热丝ＣＶＤ中硬质合金ＹＧ８上金刚石薄膜的成核，使成核期大为缩短，根据扫描电镜和拉曼光谱对沉积结果的分析，研究了ＹＧ８上金刚石薄膜成核的机理。     

硬质合金YG8上金刚石薄膜的成核研究

利用调节基底表面碳流量的方法促进了丝ＣＶＤ中硬质合金ＹＧ８上金刚石薄膜的成核，使成核期大为缩短，根据扫描电镜和拉曼光谱对沉积结果的分析，研究了ＹＧ８上金刚石薄膜成核的机理。     

WC-Co硬质合金表面MW-PCVD制备金刚石薄膜去钴预处理的研究

研究了ＷＣ－Ｃｏ硬质合金刀具表面微波等离子体化学气相沉积（ＭＷ－ＰＣＶＤ）制备金刚石薄膜时不同的去钴预处理方式的影响。扫描电子显微镜形貌观察和喇曼谱分析表明，利用氢－氧等离子体处理方式有显著的去钴效果，相应沉积获得的金刚石薄膜质量相对较高。与酸腐蚀处理相比，微波等离子体化学气相沉积装置中实现氢－氧等离子体处理方式具有独特的优越性。     

WC—Co硬质合金表面MW—PCVD制备金刚石薄膜去钴预处理的研究

研究了ＷＣ－Ｃｏ硬质合金刀具表面微波等离子体化学气相沉积（ＭＷ－ＰＣＶＤ）制备金刚石薄膜时不同的去钴预处理方式的影响。扫描电子显微镜形貌观察和喇曼谱分析表明，利用氢－氧等离子体处理方式有显著的去钴效果，相应沉积获得的金刚石薄膜质量相对较高。与酸腐蚀处理相比，微波等离子体化学气相沉积装置中实现氢－氧等离子体处理方式具有独特的优越性。     

薄膜技术

薄膜技术９９０８００１　提高金刚石膜与硬质合金结合强度的新方法——ＬｅｅＤ　Ｇ．Ｓｕｒｆａｃｅ＆ＣｏａｔｉｎｇｓＴｅｃｈｎｏｌｏｇｙ,１９９８,１００～１０１（１～３）∶１８７（英文）在硬质合金上沉积金刚石膜,由于二者热膨胀系数失配,使金刚石膜内应力较大,导致金刚石膜剥离或开裂。对基材进行改性,制备三维热力学上和成分上呈梯度变化的中间层,可提高金刚石膜与硬质合金的结合强度。在硬质合金上沉积ＷＣ,提高了硬质合金表面粗糙度,从而明显改善金刚石膜的结合强度。９９０８００２　ＣＶＤ沉积薄膜的前处理——Ａ…     

微波等离子体刻蚀处理对金刚石薄膜涂层刀具附着力和切削性能的影响

用HFCVD法在硬质合金（YG6）刀具衬底上沉积金刚石薄膜,用氢微波等离子体刻蚀的方法对衬底进行表面预处理,研究了该预处理技术对WC硬质合金衬底表面成分的影响,进一步探讨了所沉积金刚石薄膜的表面形貌和附着力,并通过难加工材料实际切削试验。研究了所制备的金刚石薄膜涂层刀具的切削性能。试验结果表明,Ar-H2微波等离子体刻蚀脱碳处理是提高金刚石薄膜附着力和改善涂层刀具切削性能的有效预处理方法。     

等离子体刻蚀处理对金刚石膜粘附性能的影响

采用直流等离子体射流ＣＶＤ法在ＹＧ８质合金基体上成功地合成了多晶金刚薄膜。通常基体表面经金刚石磨盘研磨、稀硝酸化学侵蚀脱钴预处理后，沉积的金刚石薄膜的的粘附性能仍不理想。本文首次采用原位的Ａｒ－Ｈ２等离子体射流对基体表面进行适当的轰击、刻蚀处理，显著粗化了基体表面，并使基体表面显微组织和化学成分发生重大变化，并且在合适的沉积工艺条件下，沉积的金刚石膜的粘附性能显著提高。借助ＸＲＤ、ＳＥＥＭ、ＴＥＭ     

用热丝法在硬质合金基体上沉积金刚石膜的研究

用XRD，SEM和Raman光谱仪，洛氏硬度计等分析检测手段。研究了经表面两步法侵蚀后，YG15硬质合金基体上用热丝法沉积出的金刚石薄膜的晶体结构，显微组织，化学纯度及粘结性能等，结果表明，硬质合金基体表面一定深度范围内钴含量的变化。对金刚石薄膜的晶体结构取向，组织形态，化学纯度及粘结性能等有很大影响。（1）在基体表面深度约为5μm范围内，当钴含量为0.81%时，金刚厂长汪膜具有明显的{111}面取向，其金刚石纯度较高；而当钴含量为1.05%时，具有{110}和{111}面的混合取向，其金刚石纯度较低，且其薄膜具有较高的内应力。（2）当CVD沉积温度为800℃时，金刚石薄膜的晶粒度约为1-3μm。（3）与多边形金刚石薄膜相比，菱形金刚石薄膜与硬质合金基体具有较高的粘结性能。     

硬质合金表面钴含量对金刚石形核密度的影响

对比分析了经金刚石磨盘研磨、脱钴／未脱钴ＹＧ８硬质合金上蒸镀非晶碳膜预处理对金刚石形核密度的影响。结果表明，未脱钴者，金刚石的形核密度低，金刚石结晶质量差，颗粒稀少，未成膜。原因是金刚石沉积过程中，基体内部的钴会扩散或蒸发到表面，产生明显聚集和长大。而经脱钴处理者，成核密度可达１０＾８ｃｍ＾－２，颗粒尺寸１～２μｍ，金刚石结晶质量好，刻面廓分明，表面基本成膜。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...