Sn-Ag-Cu系无铅焊料性能研究进展

Sn-Ag-Cu是全球公认的最具潜力替代Sn-Pb钎料的无铅焊料。本文介绍了Sn-Ag-Cu系无铅焊料在熔化温度、润湿性、抗氧化性和焊接可靠性方面的主要性能以及最近的研究重点,最后对Sn-Ag-Cu系无铅焊料的发展趋势进行了展望。     

Sn-Ag-Cu无铅钎料粉末与合金的组织及钎焊性能对比

利用自行设计的超音速雾化制粉装置制备了Sn-3Ag-2.8Cu 无铅焊锡粉末,并将不同介质雾化的粉末组织和普通合金组织进行对比,同时选择一种综合性能良好的粉末,将其钎焊性能和普通合金进行对比.结果表明,氮气雾化粉末比空气雾化粉末具有更高的凝固速度;雾化粉末组织更细小,主要由基体上弥散分布的多边形Cu6Sn5 IMC 和粒状Ag3Sn IMC组成;粉末比普通合金与铜基板形成的IMC更不规则,且扩散层与基板的界面更模糊;雾化粉末的蠕变断裂寿命显著高于普通合金.因此,Sn-3Ag-2.8Cu无铅焊锡粉末性能优于普通合金.     

低温聚合物导体浆料粘结相的选择

本文论述了以银包玻璃微珠为导电相的低温聚合物导体浆料中树脂的选择实验,通过对所得浆料各种性能的比较,得到比较适合银包玻璃微珠的2种树脂A和F.适合的浆料配方是:35%～40%A树脂(TYI油墨类)配合使用60%～65%的导电相,30%～35% F树脂(改性聚脂4#)配合使用65%～70%的导电相.把浆料样品放置72天,阻值变化率基本在10%以内.     

老化对Sn-Ag-Cu焊料/Ni-P镀层界面结构和剪切强度的影响

对Sn-3．5Ag-0．7Cu／Ni—P界面上的焊点进行了150℃固相老化和250℃液相回流老化实验．两种条件下焊料体内和界面处金属间化合物的成分、长大速率及形貌均有较大差异．在液相回流条件下金属间化合物长大更快,对焊点的可靠性有较大的影响．延长固相老化时间,焊点内生成大尺寸的Ag3Sn相;高温液相回流有Ni3P层生成,降低焊点的焊接强度．     

Mn、Zn对低银Sn-Ag-Cu无铅钎料接头组织和性能的影响

研究了微量元素Mn和Zn对低银Sn-Ag-Cu无铅钎料钎焊接头组织和性能的影响。结果表明,Mn和Zn可使钎焊界面金属间化合物层(Cu3Sn和Cu6Sn5)变得薄而均匀;其可以增加低银钎料的钎焊接头的拉伸强度和剪切强度,最佳元素添加量为0.2%Zn和0.05%Mn(质量分数);断口形貌显示其接头为塑性断裂破坏。Mn、Zn的添加,使得钎料组织的方向性生长状态弱化,同时,可以抑制Cu6Sn5和Cu3Sn金属间化合物层在高温环境下的时效长大或粗化,表明其对接头的稳定可靠性也具有改善作用。     

航空用银铝多元合金钎料钎焊性能的研究

对自行设计加工的BAgAl合金钎料的熔化特性进行了研究,并对其润湿铺展及漫流性做了相应的试验.用该钎料真空钎焊TCA/TC4,通过金相显微镜,扫描电镜及EDS观察分析,结果表明,该钎料性能优良,在Ti及Ti合金基体上的流动性和润湿性好,钎缝圆角适中,表面光洁致密.微观分析表明,Ag和Al能够扩散到基体金属中,在钎焊界面处形成有一定的塑性的金属间化合物(Ag-Al-Ti),而钎料中的扩散层厚度随温度升高、时间延长而增加,铝可以有效抑制钛合金的溶解.     

陶瓷用Ag-Cu-Ti焊料制备工艺的研究

采用2种粉末成形制备方法，研究了Ag-Cu-Ti合金的制粉工艺、粉末成形工艺、烧结工艺、热处理工艺及片材轧制工艺，获得了成分均匀、氧含量低、厚度为0．1mm的陶瓷用Ag—Cu—Ti焊料，比较了2种成形制备工艺的性能。     

真空电子器件用V-B系列钎料研究

采用真空-充氩熔炼V-B系列钎料,并通过球磨技术制成焊料粉末.实验表明:V-B系列钎料的真空钎焊性能优良;V-B系列块状钎料瞬间熔化并快速铺开,流动性好,润湿性好,表面均匀.V-B-Pd块状钎料的熔点为1730℃,V-B块状钎料的熔点为1740℃;V-B粉末钎料铺展均匀,有明显的润湿环,钎料铺展面积约占基体面积的3/4,钎料的熔点为1560℃.     

摩托车CE摇臂组合失效分析

某公司生产的摩托车零配件CE摇臂组合，在第一次使用时即断裂。为此，应用扫描电镜、金相显微镜、ICP-AES等对其显微组织、断口形貌和硬化层深度等进行了分析，结果表明，热处理不当而产生氢脆是造成断裂的主要原因。     

ABB机器人在铸造组芯整体浸涂上的应用

ABB机器人采用了模块化设计,它将控制器功能按逻辑划分为控制、轴驱动和过程控制等三个独立模块,配备符合人机工程学设计的全新便携式接口装置FlexPendant,从而实现工业上的柔性生产。本文主要介绍ABB机器人整体浸涂的过程,说明IRC机器人控制系统原理。阐述了ABB机器人取芯、浸涂、放芯程序实现过程和使用情况。     

电子行业用高纯金溅射靶材研究综述

围绕半导体集成电路产业的需求,综述高纯金提纯中杂质元素的控制,制备工艺中的金靶材结构设计、微结构调控技术及靶材与背板焊接绑定等技术的研究现状。提出通过行业协调修订相关产品标准,结合溅射设备完善靶材的结构设计,开展靶材微结构调控进行金薄膜与靶材结构的关联性研究,拓展高纯金靶材的绑定技术等研究方向。     

Thermal Spray Applications in Electronics and Sensors: Past,Present, and Future

Thermal spray has enjoyed unprecedented growth and has emerged as an innovative and multifaceted deposition technology. Thermal spray coatings are crucial to the enhanced utilization of various engineering systems. Industries, in recognition of thermal spray’s versatility and economics, have introduced it into manufacturing environments. The majority of modern thermal spray applications are “passive” protective coatings, and they rarely perform an electronic function. The ability to consolidate dissimilar material multilayers without substrate thermal loading has long been considered a virtue for thick-film electronics. However, the complexity of understanding/controlling materials functions especially those resulting from rapid solidification and layered assemblage has stymied expansion into electronics. That situation is changing: enhancements in process/material science are allowing reconsideration for novel electronic/sensor devices. This review critically examines past efforts in terms of materials functionality from a device perspective, along with ongoing/future concepts addressing the aforementioned deficiencies. The analysis points to intriguing future possibilities for thermal spray technology in the world of thick-film sensors.     

组装式电阻炉用于大型设备的现场热处理

本文介绍一种组装式电阻炉的结构特点和实际应用效果，为各种压力容器，大型设备和金属构件的焊后去应力退火提供一种更好的解决办法。     

Effect of Solder Thickness on Electromigration Behavior in Eutectic SnPb Solder Reaction Couples

The trend of miniaturization of electronic products induced the shrinking dimension of interconnects in the chip. When those interconnects are subjected to high current density (usually 10³ to 10⁴ A/cm²), electromigration (EM) could affect the reliability of the chip which would ultimately break the circuit. In this study, eutectic SnPb solders with thickness of 280, 128, and 50 μm were investigated under high current density (10⁴ A/cm²) and high ambient temperature (120 °C). The EM-induced surface undulations were more prominent at the shorter thickness, demonstrating that the diffusion of metal atoms/ions was controlled by the actual temperature in the bulk solder instead of the back stress. Bamboo groove features were observed on the surface of solder extrusion at the anode side for the three solder thickness, which indicated the metal atoms/ions that migrated parallel to the direction of flow of electrons.     

纳米银填充导电浆料的研究进展

导电浆料是发展电子元器件的基础及封装、电极和互联的关键材料。随着电子元器件向微型化、精密化和柔性化等方向发展,国内外正在开展金属导电填料纳米化的研究。其中,纳米银填充导电浆料成为该领域的研究热点。纳米银作为导电填料对银浆性能影响是正面还是负面影响还没有一个统一的结论。一般认为纳米银填充到基体中,由于粒子间的接触点面积小,填料粒子数目增多导致接触电阻增加。只有当纳米银间距离在一定范围内时,由于隧道效应等使导电性增强。这主要与其颗粒大小和形貌、表面性质和烧结行为等密切相关。本文从纳米银填充导电浆料的导电机理、纳米银低温烧结、表面处理、填量、形貌和原位添加等方面综述了国内外研究者近年来在纳米银填充导电浆方面的研究进展,并对未来的发展方向进行了展望。     

Integrating Augmented Reality in the Assembly Domain - Fundamentals, Benefits and Applications

Augmented Reality (AR) Is a new form of human-machine interaction which overlays computer-generated information on the real world environment, e.g. through a semi-transparent, head-mounted display. With AR presented information is derived from the real environment and is thus context-sensitive. Augmented Reality can there fore enhance a user's view with virtual information that is Sensitive to the current state of the surrounding real world. While Virtual Reality Technology (VRT) is commonly used in the automotive and aircraft industry, there exists few research approaches in the field of Augmented Reality. This contribution gives a detailed introduction to AR systems, and describes the capabilities and benefits of AR in the field of assembly. As an application, a modular AR system for guiding manual assembly and for use in assembly planning is described. Furthermore, a method for integrating AR into the planning process of manual assembly stations is presented.     

The observation and simulation of Sn-Ag-Cu solder solidification in chip-scale packaging

The formation of solidification defects in lead-free soldering is greatly influenced by material factors as well as the design of circuit assemblies. To establish ideal processing conditions and design concepts for sound soldering structures, defect formation in Sn-Ag-Cu for various types of circuit assemblies must be understood. In this study, the solidification process of Sn-3Ag-0.5Cu solder balls on circuit boards for a chip-scale package was examined primarily by using an in-situ solidification observation system with the aid of the solidification simulation. Microstructural observations were also carried out on soldered joints to support those observations and simulations. The experimental results correlate with the simulation results. Editor’s Note: Some of the figures in this article were captured from video clips during in-situ observation. Although these figures do not reflect JOM’s usual standards for publication, they are considered essential illustrations of this work. For more information, contact Keun-Soo Kim, Osaka University, Institute of Scientific and Industrial Research, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan; +81-6-6879-8521; fax +81-6-6879-8522; e-mail kskimm12@sanken.osaka-u.ac.jp.     

航空发动机叶片Tc4材料的非线性累积损伤及可靠度研究

以轴向拉压疲劳试验统计航空发动机叶片TC4材料在不同应力比下的损伤及寿命分布,针对线性损伤模型的不足,基于Chaboche非线性损伤模型和第四强度理论,提出叶片TC4材料的非线性损伤演化方程,并引入W?hler曲线和BP神经网络计算结果进行比较。以压气机叶片在最大连续工作状态下流场仿真计算结果为依据,计算出叶片应力时间历程。基于应力强度干涉模型,从能量耗散角度描述TC4材料的剩余强度模型结合泊松随机过程,完成航空发动机压气机叶片在最大连续工作状态下的可靠度预测。     

步进式液压数字阀用永磁式步进电动机的非线性控制

通过现代非线性理论如混沌动力学理论研究了永磁式步进电动机的非线性动力学。本文的研究对象是三相步进电动机。研究表明在高频情况下系统会经历一个动态的分又(Hopf分叉)。由于步进电动机作为步进式液压数字阀的电气一机械转换元件被广泛地应用于液压数字压力阀、液压数字流量阀、液压数字方向阀。本文提出了对三相步进电动机的不稳定性的控制,设计了非线性鲁棒控制器,阐明了在一些电动机参数不确定的情况下,如何使系统稳定,并且具有令人满意的性能。     

磁致伸缩材料的特性及应用研究（Ⅰ）

回顾总结了磁致伸缩材料的及其在器件方面的应用,对以该材料为核心的各种器件性能作了阐述并与Ｐｂ（Ｚｒ,Ｔｉ）Ｏ２（ＰＺＴ）压电材料进行比较。报道了武汉理工大学开展的超精密微位移致动器和磁场光纤传感等方面的研究,并对该材料今后的应用进行了展望。