Volcanism Pacing Slumping Gravity Flow Deposits during the Late Carboniferous in the Southern Margin of the Junggar Basin,China

Deep-water gravity depositional processes and evolution in arc systems have become topics of intense research focus in recent years.This study discusses the co-evolution of volcanism and deep-water gravity flow deposits at the southern margin of the Junggar Basin,based on petrology,geochronology and geochemical analyses.The results show that a massive collapse of unstable sediments from the slope was triggered by volcanism,resulting in the formation of slumping gravity flows.The occurrence of volcanic beds in the slump deposits confirm that synchronous volcanism likely affected sediment instability,triggering gravity flows.The Th/Yb,Ta/Yb and Th/Ta elemental ratios,U-Pb ages of detrital zircons and paleocurrent directions indicate that the North Tianshan(NTS)island arc represents the provenance of the Qianxia Formation.Moreover,statistical data on the pyroclastic components in the gravity flow deposits reveal an intensity index of volcanism,indicating that volcanism is strongly related to gravity flow deposits,especially in terms of the type and distribution of the deposits.A model for volcanically-triggered deep-water gravity flow deposits is established,in order to provide a more in-depth understanding of the co-evolution of volcanism and gravity flow deposits within the depositional setting of the late Paleozoic NTS oceanic subduction margin in the Junggar Basin.

Optical and electrical properties of BaSnO_(3) and In_2O_(3) mixed transparent conductive films deposited by filtered cathodic vacuum arc technique at room temperature

For the crystalline temperature of BaSnO_(3)(BTO)was above 650℃,the transparent conductive BTO-based films were always deposited above this temperature on epitaxy substrates by pulsed laser deposition or molecular beam epitaxy till now which limited there application in low temperature device process.In the article,the microstructure,optical and electrical of BTO and In_(2)O_(3) mixed transparent conductive BaInSnO_(x)(BITO)film deposited by filtered cathodic vacuum arc technique(FCVA)on glass substrate at room temperature were firstly reported.The BITO film with thickness of 300 nm had mainly In_(2)O_(3) polycrystalline phase,and minor polycrystalline BTO phase with(001),(011),(111),(002),(222)crystal faces which were first deposited at room temperature on amorphous glass.The transmittance was 70%–80%in the visible light region with linear refractive index of 1.94 and extinction coefficient of 0.004 at 550-nm wavelength.The basic optical properties included the real and imaginary parts,high frequency dielectric constants,the absorption coefficient,the Urbach energy,the indirect and direct band gaps,the oscillator and dispersion energies,the static refractive index and dielectric constant,the average oscillator wavelength,oscillator length strength,the linear and the third-order nonlinear optical susceptibilities,and the nonlinear refractive index were all calculated.The film was the n-type conductor with sheet resistance of 704.7Ω/□,resistivity of 0.02Ω⋅cm,mobility of 18.9 cm2/V⋅s,and carrier electron concentration of 1.6×10^(19) cm^(−3) at room temperature.The results suggested that the BITO film deposited by FCVA had potential application in transparent conductive films-based low temperature device process.

Experimental Research of DLC Film Deposited by Filtered Vacuum Arc Evaporation

本文研究了过滤式阴极电弧沉积方法获得的类金刚石薄膜．实验研究电弧的稳定性和探针电流与沉积参数的关系，并系统研究了膜层的性能．膜层的摩擦性能也得到了研究．

Tribological properties of diamond-like carbon films deposited bv pulsed laser arc deposition

A novel method, pulsed laser arc deposition combining the advantages of pulsed laser deposition and cathode vacuum arc techniques, was used to deposit the diamond-like carbon （DLC） nanofilms with different thicknesses. Spectroscopic ellipsometer, Auger electron spectroscopy, x-ray photoelectron spectroscopy, Raman spectroscopy, atomic force microscopy, scanning electron microscopy and multi-functional friction and wear tester were employed to investigate the physical and tribological properties of the deposited films. The results show that the deposited films are amorphous and the sp2, sp3 and C-O bonds at the top surface of the films are identified. The Raman peak intensity and surface roughness increase with increasing film thickness. Friction coefficients are about 0.1, 0.15, 0.18, when the film thicknesses are in the range of 17-21 nm, 30-57 nm, 67-123 nm, respectively. This is attributed to the united effects of substrate and surface roughness. The wear mechanism of DLC films is mainly abrasive wear when film thickness is in the range of 17-41 nm, while it transforms to abrasive and adhesive wear, when the film thickness lies between 72 and 123 nm.

FUNDAMENTAL PROBLEMS IN PULSED-BIAS ARC DEPOSITION

Arc deposition, a widely used surface coating technique, has disadvantages such as large droplet size and high deposition temperature. Recent trend in its renovation is the introduction of pulsed bias at the. substrate. The present paper attempts to describe the deposition process of TiN films using this technique with emphasis laid on the understanding of the basic problems such as discharge plasma properties, temperature calculation, and droplet size reduction. We show that this technique improves the film micro structure and quality, lowers deposition temperature, and allows coatings on insulating substrates. After analyzing load current oscillation behaviors, we have determined that the plasma load is of capacitance nature due to plasma sheath and that it is equivalent to a circuit element consisting of parallel capacitance and resistance. At last, we point out the remaining problems and future development of the pulsed-bias arc deposition technique.

Post-ore Modification and Preservation of the Indosinian Porphyry Copper Deposit in Geza Arc, Yunnan, SW China

Objective The post-ore modification and preservation of porphyry copper deposits is controlled and influenced by various geological processes, and the regional uplift and denudation is the most important factors. This study used biotite mineral geobarometer and Apatite Fission Track （AFT） to restore the uplift evolution of the granitic porphyries in the Geza arc and to obtain quantitative data of rock erosion degree and denudation rate.

Effect of pulsed bias on the properties of ZrN/TiZrN films deposited by a cathodic vacuum arc

ZrN/TiZrN multilayers are deposited by using the cathodic vacuum arc method with different substrate bias（from 0 to 800 V）,using Ti and Zr plasma flows in residual N 2 atmosphere,combined with ion bombardment of sample surfaces.The effect of pulsed bias on the structure and properties of films is investigated.Microstructure of the coating is analyzed by X-ray diffraction（XRD）,and scanning electron microscopy（SEM）.In addition,nanohardness,Young＇s modulus,and scratch tests are performed.The experimental results show that the films exhibit a nanoscale multilayer structure consisting of TiZrN and ZrN phases.Solid solutions are formed for component TiZrN films.The dominant preferred orientation of TiZrN films is（111） and（220）.At a pulsed bias of 200 V,the nanohardness and the adhesion strength of the ZrN/TiZrN multilayer reach a maximum of 38 GPa,and 78 N,respectively.The ZrN/TiZrN multilayer demonstrates an enhanced nanohardness compared with binary TiN and ZrN films deposited under equivalent conditions.

Cathodic micro-arc electro-deposition of ZrO_2 coatings in an aqueous solution containing colloidal particles

By a novel technique-cathodic micro-arc electro-deposition (CMED), ZrO_2coatings were deposited on an FeCrAl alloy. Experimental results show that the necessary conditionsfor obtaining ZrO_2 coatings are to apply a pulse peak voltage over a critical value and addmoderate amounts of ZrO_2 colloidal particles and Zr(NO_3)_4 in the aqueous solution. Theas-deposited coatings are porous because hydrogen, water, and other vapors are generated andreleased from the coatings to the solution during the spark reaction. The coatings containmonoclinic and tetragonal crystalline ZrO_2 with certain degree of amorphous structure. Theprocessing parameters and mechanism of CMED were discussed.

Preparation and tribological properties of DLC/Ti film by pulsed laser arc deposition

This paper reports that DLC （diamond like carbon）/Ti and DLC films were prepared by using pulsed laser arc deposition. R-ray diffraction, Auger electron spectroscopy, Raman spectroscopy, atomic force microscopy, nanoindenter, spectroscopic ellipsometer, surface profiler and micro-tribometer were employed to study the structure and tribological properties of DLC/Ti and DLC films. The results show that DLC/Ti film, with I（D）/I（G） 0.28 and corresponding to 76% sp3 content calculated by Raman spectroscopy, uniform chemical composition along depth direction, 98 at% content of carbon, hardness 8.2 GPa and Young＇s modulus 110.5 GPa, compressive stress 6.579 GPa, thickness 46 nm, coefficient of friction 0.08, and critical load 95mN, exhibits excellent mechanical and tribological properties.

Micro arc oxidation and electrophoretic deposition effect on damping and sound transmission characteristics of AZ31B magnesium Alloy

Micro arc oxidation(MAO) and electrophoretic deposition(EPD) process are employed to fabricate a dense coating on magnesium alloy to protect it from corrosion in engineering application. The EPD film changes the damping characteristic of magnesium alloy, and both the MAO and EPD process change the bending stiffness of samples being treated. Damping loss factor(DLF) test and sound transmission experiments were carried out for AZ31 B magnesium alloy with coating fabricated by MAO and EPD processes. The results indicate that DLF is improved in frequency range from 0-850 Hz. Bending stiffness of the samples is improved with MAO and EPD treatment. As a result, the sound transmission loss(LST) is improved in the stiffness control stage of the sound transmission verse frequency curve. To the samples by electrophoresis process, the LST is improved in frequency range from 2500-3200 Hz, because the damping loss factor is improved with EPD process. The results are useful for the surface treatment to enhance the damping loss factor, LST and widespread application of magnesium alloy while improving the corrosion resistance.

Numerical analysis on the effect of process parameters on deposition geometry in wire arc additive manufacturing

Here we develop a two-dimensional numerical model of wire and arc additive manufacturing(WAAM)to determine the relationship between process parameters and deposition geometry,and to reveal the influence mechanism of process parameters on deposition geometry.From the predictive results,a higher wire feed rate matched with a higher current could generate a larger and hotter droplet,and thus transfer more thermal and kinetic energy into melt pool,which results in a wider and lower deposited layer with deeper penetration.Moreover,a higher preheat temperature could enlarge melt pool volume and thus enhance heat and mass convection along both axial and radial directions,which gives rise to a wider and higher deposited layer with deeper penetration.These findings offer theoretical guidelines for the acquirement of acceptable deposition shape and optimal deposition quality through adjusting process parameters in fabricating WAAM components.

Diagnosis of gas phase near the substrate surface in diamond film deposition by high-power DC arc plasma jet CVD

Optical emission spectroscopy （OES） was used to study the gas phase composition near the substrate surface during diamond deposition by high-power DC arc plasma jet chemical vapor deposition （CVD）. C2 radical was determined as the main carbon radical in this plasma atmosphere. The deposition parameters, such as substrate temperature, anode-substrate distance, methane concentration, and gas flow rate, were inspected to find out the influence on the gas phase. A strong dependence of the concentrations and distribution of radicals on substrate temperature was confirmed by the design of experiments （DOE）. An explanation for this dependence could be that radicals near the substrate surface may have additional ionization or dissociation and also have recombination, or are consumed on the substrate surface where chemical reactions occur.

STUDIES OF Cr-O THIN FILNS DEPOSITED BY MULTI-ARC ION PLATING

This paper presents the formation of Cr-O thin films on an iron substrate by multi-arc ion plating, which are intended to be used as a thermal radiation absorbent in electronic vacuum devices. Only oxygen was used as a reaction gas during deposition, the Cr-O thin film, must have high adhesion and low outgassing rate. The scratch test shows that the critical load, for an applicable Cr-O thin film deposited in oxygen atmosphere alone at a pressure of 8×10-1 Pa, was as high as 6kg.

Fabrication of Tungsten Carbide Films by Filtered Pulse Arc Deposition with Cemented Tungsten Carbide Cathodes

Tungsten carbide films (W-C films) were fabricated on silicon substrates by using the filtered pulse arc deposition (FPAD) method. Two types of cemented tungsten carbide (WC) were used as cathode, one containing Co and the other Ti, which were used as binders for forming the cathode shape. The films were fabricated by varying the pulse arc current and substrate bias voltage. The discharge, deposition and film properties were investigated under these deposition conditions. The cathode wear amount when using WC-Co (WC cathode containing Co) was found to be smaller than that measured when WC-Ti (WC cathode containing Ti) was used. The W-C film thickness was approximately 30 - 40 nm under all conditions, except when the pulse arc current was 50 A and the film thickness, was approximately 10 nm. Compared to the WC-Ti, the consumption of cathode material is suppressed in the WC-Co, indicating that the efficiency for film preparation of the latter is good. From the X-ray diffraction analysis, the crystalline phase of W-C films fabricated using WC-Co and WC-Ti were observed as W2C and WC1-x, respectively, indicating that different crystalline phases could be fabricated using different cathodes. From the X-ray photoelectron spectroscopy analysis, the oxidation layer formed by air exposure was observed to exclusively exist on the W-C film surface. Moreover, almost all oxygen in the oxidation layer bonded with tungsten.

Deposition of TiN Films by Novel Filter Cathodic Arc Technique

笔直地磁性的过滤弧来源被用来存钛氮化物的薄存款。这些电影的性质强烈取决于免职过程。锡电影能被在大约 300eV N-2 (+) 氮离子轰炸考虑 Ti+ 离子横梁在氮气氛或到不偏的底层上直接扔到激烈的底层上。在后者盒子中，电影 stoichiometry 从 N 被改变: 由控制到达的 0.6-1.1 的 Ti 比率 Ti 和氮离子评价。同时，简单模型被用来把压缩应力的进化描述为到达比率的功能和帮助离子的 TiNfilms 的作文。

The Copper Thin Layer Deposition by Pulse Vacuum-Arc Sprayer

In this work, the deposition process features of a copper coating on stainless steel substrate, using the pulse vacuum arc spraying method were researched. A continuous layer of copper was deposited on a stainless steel substrate, and a high degree of coating adhesion to the substrate was demonstrated. The thickness of coating using application time was calculated, and the surface unevenness was estimated. Inside the coating layer substrate material elements were observed, that could appear as a result of simultaneously plasma spraying on the surface of the substrate. The feature of this method was discovered, that surface plasma plays a significant role in the deposition process. Finally, it was shown that the device with a pulsed arc could effectively be used in industry, since it is possible to change the layer thickness in the range of hundreds of microns by varying the deposition time.

2219铝合金CMT电弧增材熔滴过渡行为

在冷金属过渡(cold metal transfer,CMT)电弧增材制造过程中,熔池的流动行为极易受到电弧和熔滴的影响,从而严重影响堆积层的稳定性和成形件质量.该文利用高速摄影结果及电信号参数波形图,引入热输入量计算公式,从特征电信号、熔滴过渡特征量、热输入量等方面定量分析了CMT+P模式下送丝速度及脉冲修正系数对熔滴过渡过程及单道成形形貌的影响,同时分析了脉冲变极性冷金属过渡(Advanced CMT,CMT+PA)模式下送丝速度及控制面板上的EP/EN修正系数η对熔滴过渡过程及单道成形形貌的影响,为后续工艺优化提供参考和指导.

等离子电弧双丝增材制造Ti-48Al合金组织特征

采用等离子电弧双丝增材制造技术成功制备了Ti-48Al合金(at.%),并对其沉积态和热处理后的组织特征进行了系统地研究.结果表明,沉积态Ti-48Al合金主要由α2相和γ相组成,沿着沉积方向,沉积态组织呈现由树枝晶区和片层晶团区交替分布的不均匀性特征,并且在树枝晶区存在严重的枝晶间Al元素偏析现象.在1 340℃/10 h/炉冷热处理后,不均匀的沉积态组织转变为晶粒尺寸细小的双态组织,Ti-48Al合金的微观组织的不均匀性获得明显改善,并且α2相含量显著增加,组织的择优取向减弱.

沉积策略对电弧增材制造5356铝合金显微组织、缺陷和力学性能的影响

基于电弧增材制造技术(WAAM)研究往复扫描(RS)、振荡扫描(OS)和垂直扫描(VS)3种沉积策略对5356铝合金(AA5356)构件的影响,探讨5356铝合金构件的显微组织、缺陷和力学性能。结果表明:相比于RS和OS策略,VS策略使得构件的热量分布均匀。VS策略的显微组织主要由等轴晶组成,使得显微硬度最高值达到HV 77.25。VS策略使得构件的气孔率和微孔尺寸分别下降了45.52%和19.81%,从而改善了拉伸性能。因此,VS策略为获得显微组织均匀、力学性能优异的AA5356构件提供了一种新的解决方案。

矿热炉烟道颗粒沉积机理的数值研究

为了探究RKEF工艺中颗粒形状及尺寸对烟道颗粒沉积率的影响,基于计算流体力学(CFD)和Det Norske Veritas(DNV)理论,建立了烟道中炉气-颗粒气固两相的多尺度的颗粒沉积模型,精确预测了烟道中颗粒的沉积位置和沉积质量,并通过数值模拟来探究烟道内的沉积率与颗粒大小及形状之间的关系。