首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 93 毫秒
1.
为了解决CFC与Cu Cr Zr合金的冶金连接问题,以二元合金Cu62Mn38(at.%)为基础成分,采用低熔点Ga作为主要合金化元素和微合金化元素Cr和Si,设计了系列固溶体钎料合金Cu62Mn37-xGaxCr0.5Si0.5(x=0~10,at.%)。利用电弧熔炼、铜模吸铸和冷轧制备了100μm厚的钎料箔带。采用Cu62Mn31Ga6Cr0.5Si0.5钎料在不同工艺条件下(875~900℃,保温15~25min)制备了无氧铜和Cu Cr Zr合金钎焊接头。通过热分析和X-射线衍射分析了钎料熔化行为和相组成;采用光学显微镜、扫描电镜、电子探针和力学性能拉伸机对接头的组织形貌、成分分布和力学性能进行了分析。结果表明,在880℃/保温25min钎焊工艺下可获得无缺陷CFC/Cu Cr Zr接头结构,焊缝的Cu固溶体基体内有少...  相似文献   

2.
采用电解法分离铜后,电感耦合等离子体-原子发射光谱法直接测定了铜-银-磷钎料中磷的含量。实验表明,在1.0moI·L-1硝酸电解液中可以使铜基本电离完全,对磷的测定不产生干扰。在最佳的测定条件下,该法用于铜-银-磷钎料中磷的测定,回收率在98.3%—102.4%之间,相对标准偏差2.28%。  相似文献   

3.
赵宁  黄明亮  马海涛  潘学民  刘晓英 《物理学报》2013,62(8):86601-086601
金属熔体的黏度和表面张力都是与液态结构相关的敏感物理性质, 且存在一定的相互关系. 对于微电子封装材料而言, 黏度和表面张力均是影响其工艺性能的重要参量. 本文利用回转振动式高温熔体黏度仪测量了Sn-xCu (x = 0.7, 1.5, 2)钎料熔体在不同温度下的黏度值, 发现在一定温度范围内钎料熔体的黏度值存在突变, 可划分为低温区和高温区. 在各温区内, 黏温关系很好地符合Arrhenius方程, 在此基础上讨论了液态钎料的结构特征和演变规律. 同时, 利用黏度值计算了液态Sn-xCu钎料在相应温度下的表面张力, 并通过Sn-xCu钎料在Cu基板上的润湿铺展实验对计算结果进行验证. 结果显示, 润湿角和扩展率的测试结果与表面张力的计算结果具有很好的一致性, 表明通过熔体黏度值来计算锡基二元无铅钎料合金表面张力并评估其润湿性能的方法是可行的. 关键词: Sn-Cu钎料 黏度 表面张力 润湿性  相似文献   

4.
赵洋  庞晓辉  高颂 《光谱实验室》2011,28(4):2069-2073
研究了样品溶解和仪器测定的最佳工作条件,通过选择铬、镍元素的灵敏线为分析线,在高低标溶液中加入与样品同量的基体元素消除基体的影响,实现了用电感耦合等离子体-原子发射光谱法测定钴基钎料中铬和镍.样品加标回收率在97.5%-103.5%,用于标准样品中镍、铬的测定,标准样品测定结果与标准值相符,标准样品测定值的相对偏差在±...  相似文献   

5.
通过电弧熔炼制备了Fe75B16.67Si8.33非晶合金,通过真空钎焊获得了钨/低活化钢接头。通过对钎焊接头表面形貌、微观组织、成分和力学性能的表征,发现在1250℃保温10min下所获得的钎焊接头界面无孔洞、裂纹等宏观缺陷,接头组织中生成了Fe固溶体、Fe3B和FeWB金属间化合物,拉伸强度高达450MPa。  相似文献   

6.
为了连接W和CLF-1 RAFM钢,设计出由低活化元素组成的Fe-B-Si、Fe-B-Si-Sn、Fe-B-Si-Cr-(Sn)、Fe-B-Si-P-(Cr,Sn)、Fe-B-Si-Mn-(Ga,Sn)和Fe-B-Si-(Cr,Mn,Ga,Ta,Sn)系列Fe基非晶钎料,结合熔体快淬技术制备出非晶合金箔带,并对W/CLF-1 RAFM钢接头微结构进行了对比研究。采用X-射线衍射仪对箔带样品与焊缝进行了相鉴定;通过差热分析测量了非晶箔带的熔化温度和液相线温度;利用光学金相和电子探针分析了焊缝组织形貌和元素分布。结果表明,利用Fe-B-Si、Fe-B-Si-Cr和Fe-B-Si-Mn-Sn非晶钎料可获得结构完整的W/CLF-1钢接头;前两种钎料得到的焊缝组织基体相为α-Fe固溶体,而含Mn钎料形成的焊缝基体为马氏体组织;在高温钎焊过程中,这些Fe基非晶钎料中的高B含量促使FeWB、FeW2B2和Fe3B型金属间化合物在焊缝中形成,并有效地阻止了W元素向低活化钢基体长程扩散。所设计的低活化Fe基非晶钎料可用于W和低活化钢的连接和接头性能研究。  相似文献   

7.
氢化—AFS法测定青藏高原中草药中的微量砷,锑,硒和汞   总被引:24,自引:0,他引:24  
本文研究了氢化物发生无色散原子荧光法测定青藏高原中草药中的微量砷,锑,硒和汞的方法,在选定的最佳工作条件下,14种干扰元素的含量低于允许存在量,不影响测定,检出限(μg/mL)为:As1.3,Sb0.39,Se0.24,Hg0.44,9次测定的相对标准偏差(%)的为As2.4~4.2Sb2.5~5.6,Se3.1~5.0,Hg3.8~5.9。4个元素的回收率为94.7~105.4%本方法简便,快速  相似文献   

8.
微波溶样原子吸收法测定鲍鱼中Cu, Zn, Fe和Mn的含量   总被引:4,自引:1,他引:3  
文章报道了用微波消解技术及火焰原子吸收光谱法(FAAS)测定鲍鱼样品中铜、锌、铁、锰含量的方法,在pH值为1.0~2.0范围内测定结果稳定,Cu~(2 ),Zn~(2 ),Fe~(3 )和Mn~(2 )的含量分别在0~6.0,0~2.5,0~6.0和0~6.0μg·mL~(-1)范围内,符合比耳定律,回收率在96.4%~103.8%之间,RSD在0.2%~3.0%之间。结果表明,该方法具有省时、节约试剂、消解完全且精确度高等优点。  相似文献   

9.
火焰原子吸收光谱测定头发中的锌,铁,钙,镁   总被引:6,自引:3,他引:3  
本文研究了头发中锌,铁,钙,镁微量金属元素的火争原子吸收分光光度法的测定,方法简便,省时,具有良好的精密度和准确度,相对标准偏差分别为锌2.9%,铁1.9%,钙1.3%,镁3.4%。  相似文献   

10.
光电直读光谱法测定稀土铝合金中La,Ce,Pr,Nd,Sm ,Si,Fe,Cu   总被引:3,自引:0,他引:3  
本文报道了稀土铝合金中La,Ce,Pr,Nd,Sm,Si,Fe,Cu的光电直读光谱测定,对光源的激发方式及最佳工作条件进行了选择,应用KH-5高能预火花光源,采用单向全功率放电,先冲洗3秒,然后预燃5秒,曝光10秒。各元素谱线间无干扰,。使用固体试样,样品处理简单。经试验验证该法简便快速,精密度准确度高,含量在0.001%-0.002%之间RSD<6%,0.02%-0.3%之间RSD<3%,标准样品的测定值与准确值吻合较好,结果令人满意。  相似文献   

11.
In the search for applications for alloys developed under the philosophy of the High Entropy Alloy (HEA)-type materials, the focus may be placed on applications where current alloys also use multiple components, albeit at lower levels than those found in HEAs. One such area, where alloys with complex compositions are already found, is in filler metals used for joining. In soldering (<450 °C) and brazing (>450 °C), filler metal alloys are taken above their liquidus temperature and used to form a metallic bond between two components, which remain both unmelted and largely unchanged throughout the process. These joining methods are widely used in applications from electronics to aerospace and energy, and filler metals are highly diverse, to allow compatibility with a broad range of base materials (including the capability to join ceramics to metals) and a large range of processing temperatures. Here, we review recent developments in filler metals relevant to High Entropy materials, and argue that such alloys merit further exploration to help overcome a number of current challenges that need to be solved for filler metal-based joining methods.  相似文献   

12.
本文研究了贵金属标准溶液除氯离子的有关问题,解决了高纯硝酸银中贵金属等杂质元素的标样配制,以硝酸银直接压样于普通电极中直流电弧激发,可测定99.0~99.99%的高纯银,该方法简便、快速、准确。  相似文献   

13.
赵博文  尚海龙  陈凡  石恺成  李荣斌  李戈扬 《物理学报》2016,65(8):86801-086801
由于润湿性不佳, 难以实现金属钎料对陶瓷的无过渡层直接钎焊, 本文在研究了溅射Al薄膜对AlN的“润湿”作用的基础上, 通过磁控溅射的方法在AlN表面沉积Al基薄膜作为钎料, 在真空条件下对AlN陶瓷进行了直接钎焊. 采用高景深光学显微镜、扫描电子显微镜和X射线能量分散谱表征了钎焊接头和剪切断口的组织及形貌. 结果表明, 高能量溅射Al粒子对AlN的撞击可以形成只有850 ℃以上高温才可获得的Al-N化学键, 实现Al对AlN的“润湿”, 使Al基薄膜钎料能够在较低的温度(≥ 510 ℃)对AlN直接钎焊. 此方法获得的Al/AlN接头的剪切强度达到104 MPa, 含3.8 at.% Cu的Al合金钎料接头强度可进一步提高到165 MPa, 它们的剪切断裂都产生于钎缝金属之中; 增加钎料中的Cu含量至9.1 at.%后, Cu在钎缝与陶瓷界面的偏聚使接头的剪切强度降低为95 MPa. Al-20 at.% Ge合金可以将钎焊温度降低至510 ℃, 但Ge在钎缝与陶瓷界面的偏聚使接头在48 MPa发生断裂.  相似文献   

14.
Ma Z  Zhao W  Yan J  Li D 《Ultrasonics sonochemistry》2011,18(5):1062-1067
Ultrasonic-assisted brazing of Al4Cu1Mg and Ti6Al4V using Zn-based filler metal (without and with Si) has been investigated. Before brazing, the Ti6Al4V samples were pre-treated by hot-dip aluminizing and ultrasonic dipping in a molten filler metal bath in order to control the formation of intermetallic compounds between the Ti6Al4V samples and the filler metal. The results show that the TiAl(3) phase was formed in the interface between the Ti6Al4V substrate and the aluminized coating. For the Zn-based filler metal without Si, the Ti6Al4V interfacial area of the brazed joint did not change under the effect of the ultrasonic wave, and only consisted of the TiAl(3) phase. For the Zn-based filler metal with Si, the TiAl(3) phase disappeared and a Ti(7)Al(5)Si(12) phase was formed at the interfacial area of the brazed joints under the effect of the ultrasonic wave. Due to the TiAl(3) phase completely changing to a Ti(7)Al(5)Si(12) phase, the morphology of the intermetallic compounds changed from a block-like shape into a lamellar-like structure. The highest shear strength of 138MPa was obtained from the brazed joint free of the block-like TiAl(3) phase.  相似文献   

15.
氩孤钎焊加热区比热流分布的动态分析   总被引:9,自引:0,他引:9  
王忠平  贺勇 《光子学报》1996,25(1):90-95
通过对不同弧长、不同电流氩弧的高速摄影拍摄以及利用影片数据分析处理系统对其动态过程的研究,发现用高斯函数模拟氩弧钎焊加热区的比热流q(r)分布特性时,理论计算值与测量值符合得较好.实验结果表明,氩弧钎焊时采用大电流的焊接规范既不经济亦无必要.因为,由q(r)分布模型可知,当弧长不变增加焊接电流时,氩弧钎焊加热区半径变小,而qm急剧增大,往往诱发液态钎料过热,毛细填充作用不强等问题,使钎焊质量下降;当焊接电流不变增加弧长时,加热区半径显着增大,qm减小,反而有利于保证氩弧钎焊质量和生产效率.  相似文献   

16.
在采用商用的STEMET-1101非晶钎料、温度为710~750°C的真空钎焊下,对CFC/OFC(氯氟烃/无氧铜)复合块与CuCrZr(铬锆铜)的钎焊进行了研究。首先,通过X-射线衍射(XRD)和差式扫描量热分析对钎料的结构和熔化行为进行了表征;然后,通过光学显微镜、电子探针微分析和拉伸试验等方法对焊缝的组织形貌、元素成分分布、相结构和力学性能进行了分析;最后,通过高热负荷装置对CFC/OFC/CuCrZr钎焊模块的热疲劳性能进行测试。结果表明,在710~750°C钎焊温度内焊缝由Cu固溶体、(Cu, Ni)3P和Ni(Cu ,Cr)2P金属间化合物组成,焊缝平整无裂纹;特别是在750°C/15min情况下,抑制了焊缝金属间化合物的连续分布,OFC/CuCrZr的焊接强度大于OFC的抗拉强度,CuCrZr/CuCrZr的结合强度为210MPa,并呈现部分韧性断裂。在750°C/15min情况下制备的CFC/Cu/CuCrZr模块可以承受1000次7MW·m-2的循环热负荷。  相似文献   

17.
The brazing process of chlorofluorocarbon/oxygen-free-copper (CFC/OFC) composite mockup and CuCrZr at 710~750°C by vacuum brazing and with STEMET-1101 amorphous filler is studied. Firstly, the microstructure and melt behaviors of the filler are characterized by means of XRD and differential scanning calorimetry and then the organism form, elemental distributions, phase structures, and mechanical property in the bonding seams are studied by using optical microscopy, electron probe microanalysis and tensile tests. The thermal fatigue property of CFC/OFC/CuCrZr brazing mockup is measured with the high heat flux facility. The results show that the bonding seam consists of Ni(Cr, Cu)2P particles, Cu(Ni)3P phase and Cu matrix in brazing temperature of 710~750°C, which is smooth and crack-free. Especially, a continued intermetallic phase network in the bonding seam is depressed in the case of 750°C/15min treatment. The welding strength of the OFC/CuCrZr is higher than tensile strength of OFC. The bonding strength of CuCrZr/CuCrZr joint is 210MPa and fracture is partly ductile. The CFC/Cu/CuCrZr mockup prepared in the case of 750°C/15min treatment can tolerate 7MW·m-2 high heat flux under 1000 cycles.  相似文献   

18.
In the present study, different amounts of graphene nanosheets (GNSs) were added to the 4043 aluminum alloy powders by using the mechanical alloying method to produce the composite filler wires. With each of the produced composite filler wires, one all-weld metal coupon was welded using the gas tungsten arc (GTA) welding process. The microstructure, mechanical properties and fracture surface morphology of the weld metals have been evaluated and the results are compared. As the amount of GNSs in the composition of filler wire is increased, the microstructure of weld metal was changed from the dendritic structure to fine equiaxed grains. Furthermore, the tensile strength and microhardness of weld metal was improved, and is attributed to the augmented nucleation and retarded growth. From the results, it was seen that the GNSs/Al composite filler wire can be used to improve the microstructure and mechanical properties of GTA weld metals of aluminum and its alloys.  相似文献   

19.
The crystalline structure, surface morphology, electrical, and optical properties of thin films of nanocomposites consisting of silver nanoparticles embedded in poly(p-xylylene) matrix prepared by low-temperature vapor deposition polymerization were studied. Depending on the filler content, the average size of silver nanoparticles varied from 2 to 5 nm for nanocomposites with 2 and 12 vol.% of silver, correspondingly. The optical adsorption in the visible region due to surface plasmon resonance also exhibited a clear correlation from silver content, revealing a red shift of the adsorption peak with the increase of the metal concentration. The temperature dependences of the dc resistance of pure p-xylylene condensate and p-xylylene–silver cocondensates during polymerization as well as temperature dependences of the formed poly(p-xylylene)–silver nanocomposites were examined. The observed variation of the temperature dependences of electrical resistance as a function of silver concentration are attributed to different conduction mechanisms and correlated with the structure of the composites. The wide-angle X-ray scattering and AFM measurements consistently show a strong effect of silver content on the nanocomposite structure. The evolution of the size of silver nanoparticles by thermal annealing was demonstrated.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号