Improvement of the time dependent degradation characteristics of micro-soldered joints

改善微焊点随时间变化的退化特性

基本信息

批准号：
63850158
负责人：
OKAMOTO Ikuo
金额：
$ 8.19万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1989
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-63850158/
关键词：
Soldering Aging Solder alloys Mechanical properties Intermetallic compounds Eutectic alloys Cooling rate Degradation of joints はんだ拡散銅合金 CuーSn化合物熱疲労

项目摘要

Improvement of the time dependent degradation of micro-soldered joints was investigated. The obtained results are summarized as follows.1) Mechanical properties and room temperature aging characteristics: The effect of cooling rate and room temperature aging of various solder alloys on mechanical properties were studied. Sn-Ag, Sn-Sb and Pb-Ag-Sn solder alloys showed larger tensile strength with increasing cooling rate, on the other hand, in Sn-Pb solder the tensile strength was decreased with increasing the cooling rate. Precipitation of intermetallic compounds was found to be room temperature aging process.2) Thermal fatigue of solder alloys: Thermal fatigue test on Sn-40Pb-0-25Bi solder alloys revealed the alloy with 7.5- 15%Bi had good thermal fatigue resistance in spite of the lower solidus temperature. The stress relaxation rate at room temperature corresponded well with the thermal fatigue resistance of various solder alloys, therefore, the stress relaxation test could be used as a simple method to evaluate the thermal fatigue of solder alloys. Sn-7.5-15Bi, Sn-25Ag-10Sb, Pb-2.5Ag-1Sn and Sn-10Sb alloys are the candidates for making high reliable solder joints.3) Intermetallic compound growth rate: Effect of additional elements on the intermetallic compound growth was investigated on soldered various binary copper alloys. The elements preferable to be added in high strength copper lead frame alloys were silver, magnesium, manganese, zinc and tin. Such elements as iron, phosphorus, nickel, silicon, titanium, paradium, aluminum, plutinum and cobalt should not be added because the elements remarkably degraded the reliability of joints by the growth of intermetallic compounds.

研究了改善微焊接点随时间变化的退化。所得结果总结如下： 1）力学性能和室温时效特性：研究了各种焊料合金的冷却速率和室温时效对力学性能的影响。 Sn-Ag、Sn-Sb和Pb-Ag-Sn焊料合金随着冷却速率的增加表现出更大的抗拉强度，另一方面，Sn-Pb焊料的抗拉强度随着冷却速率的增加而降低。发现金属间化合物的析出是室温时效过程。 2）焊料合金的热疲劳：对Sn-40Pb-0-25Bi焊料合金的热疲劳试验表明，含7.5-15%Bi的合金尽管具有良好的抗热疲劳性能的较低固相线温度。室温下的应力松弛率与各种焊料合金的热疲劳性能具有很好的对应性，因此应力松弛试验可以作为评价焊料合金热疲劳性能的简单方法。 Sn-7.5-15Bi、Sn-25Ag-10Sb、Pb-2.5Ag-1Sn 和 Sn-10Sb 合金是制造高可靠焊点的候选合金。 3) 金属间化合物生长速率：添加元素对金属间化合物生长的影响为研究了焊接各种二元铜合金。高强度铜引线框架合金中优选添加的元素是银、镁、锰、锌和锡。不应添加铁、磷、镍、硅、钛、钯、铝、钚和钴等元素，因为这些元素会因金属间化合物的生长而显着降低接头的可靠性。