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1.
以工业纯铁表面形成Fe-11W-7Mo-23Co型合金为例,阐述了双层辉光离子多元共渗的源极成分设计思路.通过对工业纯铁表面进行W、Mo、Co多元共渗,探讨了合金元素溅射产额的不同对源极溅射成分的影响.结果表明,双层辉光离子多元共渗时,源极成分设计可以忽略合金元素溅射产额的影响.  相似文献   

2.
用能量色散X射线谱仪和电子探针,研究两种含有第二相沉淀和喷射弥散强化镍基合金的阴极溅射表面微观形貌,发现形成的溅射锥体是由于第二相沉淀和氧化物质点的存在,使局部溅射率改变和引起静电效应的结果。  相似文献   

3.
采用射频磁控溅射技术制备了Ru-B薄膜,利用掠入射X射线衍射(GIXRD)、高分辨透射电子显微镜(HRTEM)、原子力显微镜(AFM)等分析技术对薄膜的相结构、沉积速率以及表面形貌进行了研究分析。结果表明:在室温下制备的 Ru-B 薄膜均为非晶态。薄膜的沉积速率不随溅射时间变化,但随溅射功率的增加而增大。薄膜表面光滑致密质量良好,随着溅射时间的延长,薄膜表面晶粒大小和粗糙度增大。溅射功率影响着基片表面粒子的形核长大和迁移扩散速率,进而影响薄膜的表面形貌。  相似文献   

4.
针对钛表面辉光无氢渗碳技术中的电极结构,通过对辉光放电状态下等离子体中电子的作用分析,计算并优化了石墨源极与钛工件极距离、工件极和源极尺寸以及放电气体压力的数值,得出源极与工件极距离为20~40 mm,工件极的尺寸大于20 mm,源极的尺寸大于40 mm,放电气体分压大于20 Pa时,可以使电子未碰撞及几率几乎为零,能够实现石墨源极的高效溅射,并通过试验对上述结果进行了论证。  相似文献   

5.
钛合金表面双层辉光离子渗铝的研究   总被引:4,自引:3,他引:4  
利用双层辉光渗金属技术,以铝为源极、TC4(Ti-6Al-4V)为阴极、氩气为工作气体,依靠辉光放电和不等电位空心阴极效应在TC4表面形成合金层。采用X射线衍射和辉光放电光谱分析了合金层的相组成及渗层内Al元素的分布.并对其进行硬度测试。结果表明:渗层由Ti3Al和α-Ti组成;铝的含量可达18%;渗层厚度可达13μm;其硬度比经渗铝处理后的有了较大程度的提高。  相似文献   

6.
将平均晶粒度分别为30、70和150 μm的3块6N高纯纯铜方靶放在同一溅射系统中进行溅射,并检测和观察溅射后I-V特征曲线、质量损失以及所镀薄膜的表面形貌、厚度以及X射线衍射谱。结果表明,晶粒度作为靶材的一个重要参数指标,会影响靶材溅射后表面形貌和I-V特性曲线。当所镀薄膜较厚时,靶晶粒度并不会对靶的质量损失以及薄膜结晶情况产生太大的影响,但会对薄膜沉积率产生较大影响。  相似文献   

7.
黄铜拉链化学镀锡工艺研究   总被引:4,自引:2,他引:2  
周栋  王瑀  丁毅  马立群 《表面技术》2010,39(2):58-60
研究了一种黄铜表面化学镀锡工艺。通过实验,在黄铜条和黄铜拉链上得到了一种较好的银白色镀层。用扫描电镜(SEM)方法测量了镀层厚度和表面形貌,用能谱成分分析(EDS)方法对镀层进行了成分分析,用X射线衍射(XRD)方法进行了物相分析。并且对镀锡层的耐汗性能和结合力性能进行了测试,实验结果表明该镀层耐汗液性能、结合力好。  相似文献   

8.
对Ti-6Al-4V合金550℃的空气中渗氧60 h后的表面形貌、显微组织、成分、硬度、划刻性能和耐磨性进行研究,并与未处理的钛合金进行了比较.结果表明,渗氧后的钛合金表面粗糙度有所增加,表层形成约3.5μm厚的渗氧层,X射线衍射(XRD)检测到了锐钛矿相、金红石相、板钛矿相TiO2和Al2O3相.渗氧层的显微硬度和纳...  相似文献   

9.
用辉光光谱分析测出了纯Fe,45钢,Cr12Mo工具钢,Cr26Mo和Cr18Ni9Ti不锈钢的渗硼层中硼与合金元素的分布规律。根据测得的硼和合金元素的含量,计算了渗硼层中硼化物相的组成。经X射线衍射分析证明,计算结果是可靠的。  相似文献   

10.
用辉光光谱分析测出了纯Fe,45钢,Cr12Mo工具钢,Cr26Mo和Cr18Ni9Ti不锈钢的渗硼层中硼与合金元素的分布规律。根据测得的硼和合金元素的含量,计算了渗硼层中硼化物相的组成。经X射线衍射分析证明,计算结果是可靠的。  相似文献   

11.
In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.  相似文献   

12.
After nearly two years' tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry (SRIF), located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.  相似文献   

13.
Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.  相似文献   

14.
The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.  相似文献   

15.
The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).  相似文献   

16.
The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.  相似文献   

17.
On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes' collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.  相似文献   

18.
The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.  相似文献   

19.
This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.  相似文献   

20.
Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.  相似文献   

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