Title :
Comparison of isothermal mechanical fatigue properties of lead free solder joints and bulk solders
Author :
Andersson, Clas ; Lai, Zonghe ; Liu, Johan ; Jiang, Hairong ; Yu, Yongning
Author_Institution :
Swedish Microsystem Integration Technol. Center, Chalmers Univ. of Technol., Molndal, Sweden
Abstract :
Low cycle isothermal mechanical fatigue testing of both bulk solders and solder joints of eutectic Sn-37wt%Pb and Sn-3.5wt%Ag and Sn-4.0wt%Ag-0.5wt%Cu were carried out in a systematic manner at room temperature over a wide range of strain ranges (1%-10%). The eutectic Sn-37wt%Pb was used as a reference. Both for bulk solders and solder joints, the low cycle fatigue behavior of the solder alloys tested was found to be strongly dependent on strain rate. Regarding solder joints, both lead free solders also depicted somewhat better fatigue properties, compared to Sn-37Pb. The experimental results from both experimental methods (bulk solder specimens and solder joints) were compared. Concluding from an environmental point of view, and from the present bulk and solder joint isothermal mechanical fatigue experiments, both Sn-3.5wt%Ag and Sn-4.0wt%Ag0.5wt%Cu lead-free solders are advisable replacements to Sn-37wt%Pb.
Keywords :
copper alloys; eutectic alloys; fatigue; lead alloys; mechanical strength; silver alloys; solders; tin alloys; SnAg; SnAgCu; SnPb; eutectic solders; isothermal mechanical fatigue properties; lead free bulk solders; lead free solder joints; low cycle fatigue testing; strain rate; strain testing; Capacitive sensors; Electronic equipment testing; Environmentally friendly manufacturing techniques; Fatigue; Isothermal processes; Joining materials; Lead; Materials testing; Soldering; System testing;
Conference_Titel :
Electronic Packaging Technology Proceedings, 2003. ICEPT 2003. Fifth International Conference on
Conference_Location :
Shanghai, China
Print_ISBN :
0-7803-8168-8
DOI :
10.1109/EPTC.2003.1298763
