TY - JOUR
T1 - Effects of Thermal Reflowing Stress on Mechanical Properties of Novel SMT-SREKs
AU - Cai, Miao
AU - Liang, Yonghu
AU - Yun, Minghui
AU - Chen, Xuan-You
AU - Yan, Haidong
AU - Yu, Zhaozhe
AU - Yang, Daoguo
AU - Zhang, Guoqi
PY - 2019
Y1 - 2019
N2 - A novel silicone rubber elastic key (SREK) is proposed in this paper for surface mounting technology (SMT) applications. Effects of thermal reflowing stress on the mechanical properties of SMT-SREKs are investigated. The manufactured SMT-SREKs, which underwent various reflowing conditions in advance, are subjected to pressing force and fatigue pressing tests. Fatigue lifetime projection model and its predicted error are then assessed systematically. The thermal degradation of silicone rubber materials is illustrated through the dynamic mechanical analysis and the Fourier transform infrared spectroscopy experiments. The mechanical finite element modeling is also conducted to simulate the pressing process. The results show that the pressing force and tactility of the SMT-SREKs are strongly affected by the reflowing condition, which contributes to the degradation of the silicone rubber materials. During the fatigue pressing test, the change rate of tactility increases with the reflowing peak temperature ( T-{p} ) and is accelerated by the repeated reflowing process. Moreover, a linear model can precisely project the tactility before the fatigue pressing number of 2.0E+6 times, and the impact rate of T-{p} on tactility with the increasing fatigue pressing number can be predicted effectively by using a logarithm model.
AB - A novel silicone rubber elastic key (SREK) is proposed in this paper for surface mounting technology (SMT) applications. Effects of thermal reflowing stress on the mechanical properties of SMT-SREKs are investigated. The manufactured SMT-SREKs, which underwent various reflowing conditions in advance, are subjected to pressing force and fatigue pressing tests. Fatigue lifetime projection model and its predicted error are then assessed systematically. The thermal degradation of silicone rubber materials is illustrated through the dynamic mechanical analysis and the Fourier transform infrared spectroscopy experiments. The mechanical finite element modeling is also conducted to simulate the pressing process. The results show that the pressing force and tactility of the SMT-SREKs are strongly affected by the reflowing condition, which contributes to the degradation of the silicone rubber materials. During the fatigue pressing test, the change rate of tactility increases with the reflowing peak temperature ( T-{p} ) and is accelerated by the repeated reflowing process. Moreover, a linear model can precisely project the tactility before the fatigue pressing number of 2.0E+6 times, and the impact rate of T-{p} on tactility with the increasing fatigue pressing number can be predicted effectively by using a logarithm model.
KW - degradation
KW - fatigue lifetime
KW - mechanical property
KW - modeling
KW - Silicone rubber elastic key (SREK)
KW - surface mounting technology (SMT)
UR - http://www.scopus.com/inward/record.url?scp=85062971706&partnerID=8YFLogxK
U2 - 10.1109/ACCESS.2019.2900361
DO - 10.1109/ACCESS.2019.2900361
M3 - Article
AN - SCOPUS:85062971706
SN - 2169-3536
VL - 7
SP - 27106
EP - 27114
JO - IEEE Access
JF - IEEE Access
M1 - 8648339
ER -