焊点

I plant the radiator using current advanced welding technology, in the process do not change the steel structure, the connection point of the solder joints using ultrasonic non-automatic laser welding, weld contact surface so that greater and more uniform, and no welding slag, to ensure welding safety, strengthened the combination of the Department of Welded Joints of alkali and acid mist erosion of professional skills, enhanced anti-corrosion products, while research and development of new technologies, new materials for new product development.

我厂散热器采用当前先进的焊接工艺，在加工过程中不改变钢的结构，连接点采用超声波无焊点的自动激光焊接，使焊缝接触面更大，更均匀，且无焊渣，确保了焊接的安全性，加强了焊口结合部的耐碱和酸薄雾侵蚀等专业技术，增强了产品的防腐蚀性能，同时不断的研发新技术，新材料用于新产品的开发。

The organic saponifier often is composed of alkaline amines. Some common limitations are the potential attack of the solder joint, chemical oxidation that reduces bath life, limited effectiveness on some of the new flux compositions, and a contributor to the VOC content.

有机皂化剂一般由碱性胺组成，其主要的局限性在于可能对焊点造成腐蚀，并发生氧化反应降低焊剂清洗寿命，另外，它对某些新型焊剂清洗效果欠佳，VOC排放量较高。

Has characteristics of spot weld controlling accurately, fine electrode following character, and is widely used in car fittings and so on mechanical parts, to multiple projection welding and spot welding of .

具有焊点控制精确，电极随动性好的特点，广泛应用在汽配等机械零部件的多点凸焊和点焊上。

It has been found that although electrical failure was caused by solder joint crack, it was the underfill related failures that cause the solder joint crack.

在此基础上，揭示了倒装芯片封装的失效机理：焊点断裂是导致封装电失效的原因，而下部填充料中的损伤是引起焊点断裂的主要原因。

The results show that,the plastic strain ranges of solder joints with underfill decrease distinctly and the thermal cycle lifetimes are approximately 20 times larger than that in the case without underfill.

研究表明，有底充胶倒装焊SnPb焊点的塑性应变范围比无底充胶时明显减小，热循环寿命可提高约20倍，充胶后的焊点高度对可靠性的影响变得不明显。

In the process of Lead-free, because of the difference of lead-free solders and adjustment of technical parameter, we will face many new problems of reliability.

在无铅化进程中，由于无铅焊点焊料的不同和焊接工艺参数的调整，必然会给焊点可靠性带来许多新的影响。

It is clarified for the first time that the thermal fatigue failure of solder joint is actually a creep strain low cycle fatigue failure, and a physical model for creep fatigue crack propagation has been proposed. It was pointed out that creep strain increases in the high stress area ahead of the tip of thermal fatigue crack, results on one hand that the slide of crack tip increase, inactivation more serious and crack close length increases, the other hand, that intergranular crack exists, whose direction will affect the fatigue crack propagating.

本文首次阐明了焊点的热循环失效本质上是以焊点内循环蠕变为主要应变的低周疲劳失效，并在此基础上提出了蠕变疲劳裂纹扩展的物理模型，指出热循环裂纹前端的高应力区内，蠕变加剧，使裂纹前端滑移增加，裂纹钝化加剧，导致随后的裂纹闭合扩展长度增加；同时蠕变也使裂纹前端的高应力区出现晶间裂纹，蠕变沿晶裂纹对主裂纹扩展的影响取决于沿晶裂纹的连接方向。

When the elastic modulus is high, stress and strain are mainly concentrated at edge of the overlap region, while those in weld spot zone are relatively even; when the elastic modulus is low, stresses in the adhesive layer are small while stresses are concentrated to a certain extent at edge of the weld spot.

分析发现，胶粘剂弹性模量对接头中应力应变分布的趋势有明显影响，胶粘剂弹性模量高时，搭接区边缘附近区域应力应变高，焊点区应力应变值相对较小；弹性模量低时，焊点边缘处存在一定的应力集中，胶层中应力较小。

The number of spot-weld of thin-walled punched structures of automobile has important impacts on the automotive manufacturing cost.In order to reduce the cost,topological optimization of the spot-weld is becoming a hotspot.

汽车薄壁冲压件的焊点数量是汽车制造成本的决定性因素，为了降低成本，焊点的拓扑优化逐渐成为人们关注的热点。

Results indicate that its conductibility will be improved and its density will decrease if Ce is added into the leadfree solder.In the range of 0.03wt.% to 0.05wt.% of Ce,the wettability of the solder is improved,especially when the content of Ce is about 0.03wt.%,the grains of the micro structure in lead-free solder are smaller and more homogeneo...

结果表明，添加微量的铈后，钎料的导电性能提高，密度下降；铈含量在0.03%和0.05%时可以改善钎料的润湿性；特别是0.03%质量分数时晶粒组织最为细小均匀，焊点抗拉强度也最高；当铈含量大于0.1%时对钎料的性能产生不利影响，润湿时间升高，焊点抗拉强度大幅降低，因此稀土元素铈的最佳含量应为0.03%。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。