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1.
The evolution of the surface oxide film along the depth direction of typical aluminum alloy under medium-temperature brazing was investigated by means of X-ray photoelectron spectroscopy (XPS). For the alloy with Mg content below 2.0wt%, whether under cold rolling condition or during medium-temperature brazing process, the en-richment of Mg element on the surface was not detected and the oxide film was pure Al2O3. However, the oxide film grew obviously during medium-temperature brazing process, and the thickness was about 80 nm. For the alloy with Mg content above 2.0wt%, under cold rolling condition, the original surface oxide film was pure Al2O3. However, the Mg element was significantly enriched on the outermost surface during medium-temperature brazing process, and MgO-based oxide film mixed with small amount of MgAl2O4 was formed with a thickness of about 130 nm. The alloy-ing elements of Mn and Si were not enriched on the surface neither under cold rolling condition nor during medium-temperature brazing process for all the selected aluminum alloy, and the surface oxide film was similar to that of pure aluminum, which was almost entire Al2O3.  相似文献   

2.
Aluminum AlloysTX1IntroductionFe-Alintermetalicshavegreatpotentialitiesforstructuralapplicationsowingtotheirgoodmechanicalprop...  相似文献   

3.
硅影响银合金组织研究和探讨   总被引:1,自引:0,他引:1  
银合金中添加硅可以改善铸造性能和抗氧化变色性能,但是硅有粗化晶粒及形成低熔点共晶体的倾向,当硅超过一定量后,会带来晶粒组织粗大、产生硬点导致抛光面质量差、产生热裂、延展性恶化等问题,因此,要注意硅的加入量应控制在0.12%以内。  相似文献   

4.
用溶胶-凝胶法制备掺杂改性的二氧化钛溶胶,并选用铝片为载体,以拉膜法制得Ag-Ti-O复合膜片;用XRD、FT-IR等手段对膜片的理化性能进行表征,并以油酸作为目标降解物,分别考察了膜片在紫外光与可见光的光催化氧化性能.结果表明,改性复合膜在紫外光或可见光光照的条件下,均能有效地将附着表面的油类物质氧化分解.  相似文献   

5.
采用熔炼方法制备LZ82型镁锂合金,对合金进行常规挤压和ECAP一道次挤压,然后对合金进行光学显微组织观察、X射线衍射(XRD),并分析等通道挤压前后不同晶面相对强度的变化、宏观织构测试其各向异性的变化,从而确定合成LZ82镁锂合金的一些特性。  相似文献   

6.
NomenclatureFelectromagneticforce(EMF)B(B0)magneticfluxdensity(MFD)IcurentintheliquidmetalEvoltageinthetwoendsoftheHaldeviceR...  相似文献   

7.
The distribution of the magnetic flux density in the magnetic field generator which provided travelling magnetic field was determined. The experiments using liquid gallium and aluminum - silicon alloy to observe the turbulent flow or remove inclusions were performed to obtain the basic principles how the distribution of the magnetic flux density took effect on removing inclusions from molten metal by electromagnetic field. The suitable area in the field for purifying metal was suggested.  相似文献   

8.
本研究以二溴蒽和苯乙酮为原料,通过Sonogashira钯催化偶联反应,四氢呋喃和二乙胺混合溶剂作为偶联反应溶剂,以较高的收率获得了标题化合物,且运用IR,UV,熔点等手段进行了结构鉴定,并通过紫外光谱和荧光光谱研究了其光谱性质。  相似文献   

9.
用光学显微镜和扫描电镜(SEM)观察Al-Si合金中硅相形貌在固溶过程中的变化, 并研究了此变化对合金力学性能和断裂行为的影响. 结果表明: 固溶初期 (250 min), 硅相发生缩颈、钝化、溶断并伴随长大; 在固溶中期(250~400 min), 其形貌没有发生显著变化, 仅球化程度更高; 600 min后, 硅相的长大是受扩散控制的粗化过程, 且符合LSW粗化模型; 同时由于出现棱角小面及搭接特征使硅相形貌有所恶化. 定量金相测量及回归分析说明硅相的形貌对合金的力学性能和断裂行为有显著影响.  相似文献   

10.
研究了双环已酮草酸二腙(BCO)与铜(Ⅱ)的显色反应,建立了直接测定铝合金中微量铜的光度分析方法。在氨性缓冲溶液介质中,在表面活性剂CTMAB作用下,铜(Ⅱ)与BCO形成蓝色的配合物,配合物在606nm处有最大吸收,铜(Ⅱ)的含量在0~80μg/25mL范围内服从比耳定律,表观摩尔吸光系数为1.79×104L·mol^-1·cm^-1。该方法简便快速,应用于铝合金中铜的测定,测定结果与标准值相符,得到了满意的结果。  相似文献   

11.
1 Introduction Weight saving materials such as aluminum and its alloys are becoming increasingly important and have been attracting increasing attention over the past decade, specially in the automotive, aerospace and chemical industries, and electrical devices because of their high strength-to-weight ratio, high electrical and thermal conductivities, processability and recyclability and good resistance to degradation in some corrosive environments [1,2]. In the automotive industry, there is d…  相似文献   

12.
车身骨架作为客车的主要承载件,其轻量化对客车节能减排具有重要作用.本文以客车骨架用铝合金型材为研究对象,以车身骨架用型材的弯曲刚度和扭转刚度为指标,利用CAE分析技术分析铝合金型材代替钢的可行性.结果表明:增加壁厚和增大截面尺寸均能提高铝合金型材的弯曲刚度和扭转刚度.客车车身骨架选用截面尺寸为52 mm×56 mm,壁厚为2.4 mm的铝合金型材,其刚度能够达到40 mm×40 mm×2 mm钢制方管的刚度指标,且实现减重27.5%.计算结果可为客车车身骨架用型材设计提供参考.  相似文献   

13.
WEARPERFORMANCEANDMECHANISMOFZINC-ALUMINUM(ZA27)ALLOYSuHuaqin(苏华钦)ShiZhongliang(施忠良)ZhuMingfang(朱鸣芳)(DepartmentofMechanicalEn...  相似文献   

14.
采用熔体快淬-去合金化法制备多孔PtFe纳米材料,通过X射线衍射、扫描电子显微镜及高分辨透射电子显微镜对其结构进行了表征.并研究了其在H2O2和3,3’,5,5’-四甲基联苯胺(TMB)催化体系中作为过氧化物酶的催化活性.研究发现,此纳米酶对H2O2和TMB具有较好的亲和性能,该催化反应符合Michaelis-Menten动力学理论.  相似文献   

15.
采用热分析法对不同组成的LiOH-LiNO3二元体系进行研究,绘制了具有最低共熔点的该二元体系T-x相图。用该低共熔混合物为锂盐,与前驱体Ni0.8Co0.2(OH)2混合烧结制备出锂离子电池正极材料LiNi0.8Co0.2O2。  相似文献   

16.
用ON、XRD、SEN、EDAX等对经不同制备工艺获得的AITiB和新型AITiBRE中间合金细化剂进行了微观组织的观察分析比较。结果表明:地TiBRE中间合金中细化相主要为TiA13和TiB2,还存在着不稳定的(AITiRE)相;地TiBRE中间舍金中细化相质点的分布形态优于A13TiBRE中间合金;氟盐法所制备的地TiBRE中间合金中细化相的分布更为均匀弥散与细小,优于纯Ti粉颗粒法制备的地TiBRE中间合金的组织。  相似文献   

17.
采用MULTISPOT MI-100电阻焊机,对车身用6061-T6铝合金薄板实施电阻点焊,研究并得到电阻点焊最佳工艺参数。然后,运用正交试验方案和极差分析方法对电阻焊工艺参数进行试验和进一步优化设计。在对2mm厚度的6061-T6铝合金薄板进行搭接电阻点焊后,分析焊接外观并完成拉伸测试,测试结果表明:当焊接电流60KA、焊接压力0.63MPa、板材厚度2.00mm时,试样所获得的点焊接头无明显缺陷,成型较好,具有良好的焊接质量和外观,其抗拉剪力值最大为5.583KN。  相似文献   

18.
INTRODUCTION Mg-based alloys are considered as potentialcandidates for hydrogen storage materials because oftheir large hydrogen capacity (Reilly and Wiswall,1968; Pedersen and Larsen, 1993). However, asMg-based alloys desorb hydrogen at temperatureshigher than 600 K, they are not applicable to practicaluse. Many researches have studied to improve hy-driding/dehydriding kinetics and to lower the workingtemperature (Wang et al., 2002; Tsushio et al., 1998;Spassov and K?ster, 1998; Orim…  相似文献   

19.
Ti-Ni-Nb三元形状记忆合金较二元合金具有相当宽的相变滞后温度.本文针对Ti44-Ni47-Nb9合金中铌加入量大的特点,采用纯钛、纯镍、纯镍预制中间合金的方法,在磁悬浮水冷坩埚中进行熔炼,成分稳定可靠.经850℃锻造、轧制后,制成内径Φ12管接头.记忆合金管接头的训练在-60℃下进行,总变形量16%,用电阻法测量的相变温度为As=35℃,Ms=-120℃,滞后宽度As-Ms=155℃.还对管接头连接系统的耐水压、拉伸、扭转、疲劳性能进行了测试.  相似文献   

20.
Mg2Ni0.8Cr0.2-x wt.% CoO/Al2O3 (x=0.5, 1, 2 and 3) composites were prepared by mechanically milling sintered Mg2Ni0.8Cr0.2 alloy and CoO/Al2O3 compound for 45 h. The addition of CoO/Al2O3 compound resulted in the good kinetics properties of hydriding/dehydriding reaction of the composites. The composite with 1.0 wt.% CoO/Al2O3 catalyst could reach the maximum hydrogen absorption capacity (2.9 wt.%) within 5 min at 393 K under H2 pressure of 4 MPa, and can desorb rapidly at 493 K. The decomposition and synthesis of hydrogen molecule on Mg2Ni0.8Cr0.2 alloy surface was promoted by addition of CoO/Al2O3 catalyst. In addition, the formation of metallic Ni particles, strain and defects during the ball milling process also resulted in the improved hydrogenation performance of Mg2Ni-based alloys.  相似文献   

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