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words: Sn-Bi-Ag-Cu solder; lead free wave soldering; fillet lifting; segregation; crystalline crack 焊点剥离现象是指钎焊后立即出现的钎焊圆角从焊盘上升起的现象, 是无铅波峰焊需克服的主要缺陷之一, 频繁发生于含Bi 钎料焊点中[1], 如Sn-Ag-Bi-Cu系钎料由于合适的熔点, 良好润湿性和力学性能在波峰焊中得到了广泛应用, 但Bi添加量在2%时就有剥离现象发生, 添加量达到5%时剥离概率达到100%[2-5]. 1997年, National Center for Manufacturing Sciences首先报导了无铅钎料, 特别是含Bi和Pb污染的高锡合金钎料焊点的剥离现象, 认为钎料/焊盘间的热膨胀系数失配是焊点剥离发生的直接驱动力[6......
with trace rare earth elements [J].Electronic Mater, 2002, 31: 921-927. [19] Lin K L, Chung F C, Liu T P. The potentiodynamic polarization behavior of Pb-free Xin-9(5Al-Zn)-Ysn solders [J]. Mater Chem Phys..., wettability and mechanical properties of (Sn-9Zn)-xCu lead free solders were investigated. The addition of Cu element leads the needle Zn rich phase to transform into Cu-Zn compounds and when Cu is 8......
temperature Pb-free solders [J]. Microelectronics Reliability, 2014, 54: 1253-1273. [8] SHEN J, LIU Y C, GAO H X, WEI C, YANG Y Q. Formation of bulk Ag3Sn intermetallic compounds in Sn-Ag lead-free solders... behavior of rare-earth- containing Pb-free solders [J]. Journal of Electronic Materials, 2009, 38: 210-220. [36] YOON J W, LEE C B, KIM D U, JUNG S B. Reaction diffusions of Cu6Sn5 and Cu3Sn intermetallic......
Science, 2014, 317: 140-146. [12] TUNTHAWIROON P, KANLAYASIRI K. Effects of Ag contents in Sn–xAg lead-free solders on microstructure, corrosion behavior and interfacial reaction with Cu substrate [J... of molten lead was investigated in the temperature range of 923-1123 K. The microstructure of the lead/substrate interface was observed by SEM. The surface free energy of alumina substrates......
of lead-free solders for Sn-Pb solders. The most widely recommended lead-free solders can be divided into Sn-Ag system, Sn-Cu system, Sn-Zn system, Sn-Bi system and Sn-In system. Even though the main stream.... [2]Katsuki S. Advances in lead-free electronics soldering [J]. Current Opinion in Solid State and Materials Science, 2001, 5(1): 55-64. [3]Sung K K, Amit K S. Lead(Pb)-free solders for electronic......
of solder. The fillet-lifting can be suppressed by eliminating Pb contamination, reducing the Bi content in solder and controlling the cooling rate for solder joint. Key words: lead free wave soldering...]. 1997年National Center for Manufacturing Sciences首先报道了无铅钎料, 特别是含Bi和Pb污染的高锡合金钎料焊点的剥离现象, 认为钎料/焊盘之间的热膨胀系数失配是焊点剥离发生的直接驱动力[7]; 1998年Suganuma[8]对Sn-Bi系二元合金组织和Sn-22Bi-2Ag焊点剥离界面的微观组织进行了研究, 认为Sn-Bi系及Sn-Bi-Ag系钎......
度升高而升高.对于不含氯元素的渣系,铅的挥发气体种类为PbO和金属Pb.二者蒸汽压的对数(lnp)与温度的倒数(1/T)之间呈良好的线性关系.金属Pb蒸汽形成比例越高,总的蒸汽压越高.铅的蒸汽压随FeOT-CaO-SiO2-Al2O3 渣系碱度的升高,随FeO含量及w(Fe2+)/w(Fe3+)比例的升高而升高.对于含有Cl元素的渣系,铅的挥发气体种类为PbCl2和PbCl,二者总的蒸汽压随渣碱度及FeO含量的降低而升高. 关键词:蒸汽压;Knudsen 喷射法;金属Pb;铅氯化物;熔融处理工艺 (Edited by Yun-bin HE) Foundation item: Project supported by the Japan Oil, Gas and Metals National Corporation (JOGMEC); Project (51474021......
重金属吸附剂.本文作者开发了一步快速酯化改性麦糟新方法[8],优选次亚磷酸钠(NaH2PO2·H2O)为催化剂,N, N-二甲基甲酰胺(DMF)为反应介质,以柠檬酸与麦糟反应2 h即制备了高效的重金属吸附剂酯化改性麦糟,可用于吸附Pb(Ⅱ).本文对酯化改性麦糟吸附Pb(Ⅱ)的吸附特性,吸附动力学以及吸附机制进行系统研究,为反应器的设计和运行提供基础信息,对含铅废水处理具有重要实际意义. 1...有一定影响,利用visual MINTEQ, ver. 2.53 软件计算pH值对0.2 mmol/L铅离子在水溶液中形态的影响如图3所示.可以看出,当pH<7时,Pb主要以Pb(Ⅱ)形式存在;当pH>7时,开始形成Pb(OH)2沉淀;当pH>9时,Pb以Pb(Ⅱ)形式存在的比例仅为3%,主要以PbOH+和Pb(OH)2(aq)的形式存在,从而阻碍吸附的顺利进行,这很好地解释了高pH值不利于吸附的......
属Pb及其合金由于其在硫酸体系中优良的耐蚀性能而广泛的应用于有色金属电解提取和铅酸电池工业.但Pb及其合金也存在密度大,强度低,导电性差等缺点,这给其在实际应用中带来很多的不 便[1-4].如在有色金属电解提取工业中,其较低的强度和易蠕变性能,使电极发生变形,挠曲而引起阴阳极短接.在铅酸电池中,Pb板栅的质量占到电池总质量的20%~30%,是电池能量密度较低... 试样制备 实验选用的试剂均为分析纯,包括氯化钠(NaCl),氯化钙(CaCl2),氯化铅(PbCl2)和氯化亚锡(SnCl2),所用Al片为原铝,纯度大于99.7%. Al基体表面熔盐化学镀Pb的过程包括以下步骤:1) 熔盐准备:按要求称量一定量的干燥的氯化物,搅拌均匀,并在马弗炉中加热至设定的温度后,保温3 h;2) Al片预处理:Al片经过200#和400#砂纸打磨后,水洗......
湘南江永银铅锌矿床成矿物质来源的S,Pb同位素证据张遵遵1,2,卢友月1,2,付建明1,2,吴迎春3,程顺波1,2,马丽艳1,21. 中国地质调查局武汉地质调查中心2. 中国地质调查局花岗岩成岩成矿地质研究中心3. 湖南省地质矿产勘查开发局418队摘 要:江永银铅锌矿床是钦-杭Cu-Au-Pb-Zn-Ag多金属成矿带内典型的矽卡岩型矿床,矿床位于铜山岭岩体西部,产于岩体与围岩的接触带及其附近.矿石中金属矿物以方铅矿,闪锌矿,磁黄铁矿,黄铁矿为主.矿石金属硫化物的S,Pb同位素组成分析显示,δ34S值变化范围为0.1‰3.6‰,平均值1.7‰,组成极为均一,指示硫主要来自岩浆;矿石铅同位素组成比较稳定,206Pb/204Pb,207Pb/204Pb,208Pb/204Pb值变化范围分别为......