共查询到20条相似文献,搜索用时 922 毫秒
1.
2.
采用热弹塑性有限元方法,在考虑了材料性能参数随温度变化情况下,分析了采用Ag—Cu—Ti钎料钎焊A12O3陶瓷与Ni金属丝的钎焊接头,在钎焊和随后再次加热过程中产生的应力大小和分布情况,计算中着重考虑了钎料对接头残余应力的影响。分析结果表明,在钎料与陶瓷的界面处存在着较大的残余拉应力,影响了钎焊接头的连接强度,并可能在界面的陶瓷侧产生裂纹。通过试验对比,认为在此类连接结构中,钎料是造成接头形成较大残余应力的主要因素。同时。选择合适厚度的钎料会降低钎焊接头的残余应力,改善接头连接强度。 相似文献
3.
本文研究了Cu—Sn—Ti,Cu—In—Ti,Cu—Cr,Cu—Ge—Ti铜基活性钎料钎焊Si_3N_4陶瓷与钢。结果表明,四种铜基无银钎料均可实现Si_3N_4陶瓷与钢的连接,Cu—Sn—Ti,Cu—In—Ti的钎焊接头的剪切强度较高,它们合适的钎焊工艺参数分别为1373K×600s,1323K×600s。钎焊接头的X射线衍射分析,波谱分析表明活性钎料连接陶瓷与金属的机制是钎料中活性元素(Ti、Cu)向陶瓷界面扩散并与之发生化学反应而实现接合。 相似文献
4.
提出了一种连接Al/Ti异种合金的新工艺,即采用激光为热源,AlSi12为填充材料,实现了Ti-6Al-4V钛合金和LF6铝合金的激光熔钎焊连接。激光熔钎焊是一种局部加热焊接过程,通过调整激光加热参数,控制填充材料的润湿铺展及界面金属间化合物的形态和数量,从而控制接头质量。在实验过程中,填充焊丝实时送入,通过改变激光功率、间隙大小、光斑尺寸、焊接速度、送丝速度、激光辐照位置等工艺参数,以获得对接头的不同加热效果。研究了不同参数下的钎缝成形规律、接头界面特点及接头拉伸强度。结果表明,采用激光熔钎焊工艺连接Al/Ti异种合金可以获得成形良好、强度较高的接头,但焊接过程对工艺参数要求严格;接头厚度方向不同位置的界面金属间化合物的厚度和形态各不相同;热输入较低情况下,钎料与钛合金材料作用不充分,接头易从界面处断裂;热输入较高时,接头容易从铝合金侧熔合区附近断裂。 相似文献
5.
6.
铝软钎焊时钎料元素的化学选择吸附作用 总被引:2,自引:0,他引:2
铝软钎焊的关键问题是钎焊接头耐蚀性差。本文以普通 Pb—Sn 软钎料为基体,加入能与 Al 形成界面化合物的合金元素改变钎焊接头界面电极电位和改善钎料与母材间的结合,从而提高铝软钎钎焊接头的耐蚀性。试验研究表明:加入合金元素 Ag的 Pb—Sn 钎料钎焊 Al 时,Ag 向 Al 表面的化学选择吸附作用明显,由于形成 Ag—Al 化合物使耐蚀性显著提高。本文还提出不同工艺因素对铝软钎焊接头耐蚀性影响的试验结果。 相似文献
7.
针对微型节流制冷型红外焦平面探测器杜瓦冷指,选取TC4/Ni的钎焊形式,从钎焊方法和钎料类型的焊缝微观组织以及接头结构设计的可靠性等方面对TC4/Ni的钎焊工艺进行了研究。结果表明,结合应力、形变和降温时间仿真以及防锈蚀分析结果,研究TC4/Ni冷指端面结构钎焊工艺具有一定工程实用意义;并通过正交试验确定了高温真空钎焊+AgCu28钎料组合的较佳工艺方案,满足对控制元素偏析和减少焊接脆性相生成的目的;同时综合考虑钎透率、充耐压试验及剪切强度测试的结果,确定锥形焊缝为较佳焊接结构。 相似文献
8.
使用钎焊工艺实现微波连接器与基板互联,不但可以实现微波连接器与基板之间的机械连接,也可以实现微波连接器外壳可靠接地,使连接器装配更好地适应高频微波电路的要求。文章针对一种典型的连接器与基板垂直连接试件的焊接工艺分析,使用感应焊和电阻焊两个方法实现工艺过程,通过X射线检测钎透率,进行失效分析,并经过焊缝力学性能测试表明,通过恰当的工艺工程控制,两种方法均能够满足焊接要求。 相似文献
9.
感应钎焊技术因其具有加热迅速、焊接效率高、焊料氧化少和加热部位局域化的优点,被用来焊接微波组件中的电连接器。针对组件外形不同和待焊电连接器种类不同,设计了与组件结构相匹配的感应线圈,探索优化了感应加热参数设置。焊接获得的电连接器焊缝质量良好、气密性指标优异,满足气密封质量要求。 相似文献
10.
铝/钢异种金属无钎剂激光填粉熔钎焊接 总被引:3,自引:0,他引:3
采用宽带激光光斑和填粉焊接技术,在不使用钎剂的情况下进行6061铝合金/镀锌钢板的熔钎焊接实验。分析测试了接头成形、焊缝组织和接头强度,并探讨了影响接头强度的因素。结果表明,采用此方法可实现6061铝合金/镀锌钢板的熔钎焊连接。选用优化的焊接工艺参数获得了成形饱满,无裂纹、气孔等缺陷的焊缝。焊缝熔宽和金属间化合物层厚度随焊接热输入量的增加而增大。熔钎焊缝中金属间化合物由Al-Fe和Al-Fe-Si系统化合物组成。拉伸试样均断裂在钎料/镀锌钢界面,接头最大机械抗力为152.5 N/mm,断口呈脆性断裂特征,钎料/镀锌钢界面为接头的薄弱环节。拉伸试样铝一侧断裂面由Al5Fe2Zn0.4和α-Al组成。焊缝熔宽、金属间化合物层厚度共同决定了接头的机械抗力水平。 相似文献
11.
Mingyu Li Hongbo Xu Lee S.-W.R. Jongmyung Kim Daewon Kim 《Advanced Packaging, IEEE Transactions on》2008,31(2):399-403
This paper presents a feasibility study of using eddy current induced heating for the solder reflow of area array packages. With a high frequency electromagnetic field, Sn 3.5% Ag lead-free solder balls were heated to melt and wet the solder pads on an organic substrate. The experimental results showed that such a solder reflow process could be implemented effectively in a wide processing window. With an infrared temperature sensor, it was found that the temperature difference between the solder balls and the FR4 board might reach 80 , indicating a rather localized heating mechanism. In addition, the heating and cooling rates during the soldering were found very high. This is another feature of the induction heating reflow process. It was also found that the generated temperature in the solder balls would depend on the size of the solder balls. This characteristic may be used to perform selective soldering of flip chip BGA packages. Furthermore, the developed soldering process was applied to the board level reflow of actual components. The result verified that the induction heating reflow is a feasible soldering process in actual applications. 相似文献
12.
基于加热因子的回流曲线的优化与控制 总被引:1,自引:0,他引:1
回流焊形成的焊点质量与回流焊过程密切相关。基于加热因子Qη对回流焊接过程进行优化控制。根据焊点疲劳寿命随加热因子分布的特点,提出了对冷点加热因子取最优范围下限值控制策略(冷点代表回流过程中经历的加热因子最小焊点),以使所有焊点的加热因子尽可能都在最优范围之内。冷点下限控制策略满足了大部分焊点的高可靠性,而少部分超出最优范围上限的焊点的可靠性虽略微下降,仍可形成良好焊接。由于加热因子理论不对回流曲线形状做严格要求,定义了两个组合参数:形状参数Ht和移动参数Hb,对冷点的加热因子进行控制。并且根据统计学原理利用实验建立Qη与Ht和Hb的回归关系,发现Qη与Ht、Qη与Hb大体上成线性关系,其为Qη的预测和控制带来了极大的便利,从而使焊接可靠性易于得到保证。 相似文献
13.
14.
Kim J.H. Jihye Lee Yoo C.D. 《Components and Packaging Technologies, IEEE Transactions on》2005,28(3):493-498
An efficient ultrasonic soldering method of inserting the metal bumps into the solder is investigated in this work for electronic packaging. The effects of the process parameters such as the ultrasonic frequency, amplitude, dimensions of the metal bump and solder are analyzed through the viscoelastic modeling. The ultrasonic soldering was conducted using the Cu and Au bumps, and the acceptable bonding condition was determined from the tensile strength. Localized heating of the solder was achieved and the stirring action due to the ultrasonic influences the bond strength and microstructure of the eutectic solder. Since higher temperature is obtained with smaller solder, the proposed ultrasonic soldering method appears to be applicable to the high-density electronic packaging. 相似文献
15.
16.
The interfacial reactions at the solder joints of interest in microelectronic structures have been extensively investigated
in order to control the soldering process and thereby to provide strong and reliable solder joints. These reactions comprise
the dissolution of a base metal into a molten solder, the concomitant growth of intermetallics in the liquid state, and the
growth of intermetallics in the solid state. Various experimental techniques employed include conventional cross-sectional
metallography, scanning electron microscopy, electron microprobe analysis, x-ray diffraction and others. In this study, the
interfacial reaction between tin and copper has been investigated by using differential scanning calorimetry which provides
a simple means to study such reactions and complements information obtained from other techniques. The experimental results
have been applied to understand the interfacial reactions in two important examples: one for a soldering process with copper
metallization, and another for a high conductivity, Pb-free, electrically conducting adhesive which contains tin-coated copper
powder as conducting filler particles. 相似文献
17.
18.
19.
不同BGA封装结构的元器件在回流焊过程中,由于其焊球的受热路径和热阻不同,导致焊球受热不均匀、PCB变形甚至引起IC芯片的"虚接触",严重影响BGA元器件的焊接质量.通过对BGA封装元器件受热模型,热阻的分析,提出了不同BGA封装结构的元器件回流焊温度设置和控制要点:PBGA元器件峰值温度在235~245℃时焊接时间1... 相似文献