| Project/Area Number |
63850158
|
|---|
| Research Category |
Grant-in-Aid for Developmental Scientific Research
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
溶接工学
|
|---|
| Research Institution | Osaka University |
|---|
Principal Investigator |
OKAMOTO Ikuo Osaka Univ., Weld. Res.Inst., Professor, 溶接工学研究所, 教授 (90029009)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
FUJIUCHI Shin-ichi Nihon Genma MFG., Tech. Div., Researcher, 技術部, 研究員
SAGAWA Takaaki Tanaka PMP., Tech. Div., Chief Manager, 技術部, チーフマネジヤー
TAKEMOTO Tadashi Osaka Univ., Weld. Res.Inst., Instructor, 溶接工学研究所, 助手 (60093431)
|
|---|
| Project Period (FY) |
1988 – 1989
|
| Project Status |
Completed (Fiscal Year 1989)
|
| Budget Amount *help |
¥12,800,000 (Direct Cost: ¥12,800,000)
Fiscal Year 1989: ¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1988: ¥11,000,000 (Direct Cost: ¥11,000,000)
|
|---|
| Keywords | 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 |
|---|
| Research Abstract |
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.
|
