Evaluation of the Joint Strength of Lead-free Solder Ball Joints at High Strain Rates

고속 변형률 속도에서의 무연 솔더 볼 연결부의 강도 평가

  • Received : 2012.03.02
  • Accepted : 2012.12.13
  • Published : 2012.12.31


A lack of study on the dynamic tensile strengths of Sn-based solder joints at high strain rates was the motivation for the present study. A modified miniature Charpy impact testing machine instrumented with an impact sensor was built to quantitatively evaluate the dynamic impact strength of a solder joint under tensile impact loading. This study evaluated the tensile strength of lead-free solder ball joints at strain rates from $1.8{\times}10^3s^{-1}$ and $8.5{\times}10^3s^{-1}$. The maximum tensile strength of the solder ball joint decreases as the load speed increases in the testing range. This tensile strength represented that of the interface because of the interfacial fracture site. The tensile strengths of solder joints between Sn-3.0Ag-0.5Cu and copper substrate were between 21.7 MPa and 8.6 MPa in the high strain range.


dynamic tensile strength;lead-free solder joint;interface failure;modified charpy impact testing machin


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Supported by : 서울과학기술대학교