- HOME >
- Technical Memo >
- Shear Strength and Ductility Behavior
Shear Strength and Ductility Behavior
2019.8.8
Computer units in the automobile are
exposed to both high and low temperature. Consequently, solder joints experience
repeated stress from expansion and contraction due to the difference in the
coefficient of thermal expansion between the PCB and component, resulting in a
crack in the solder joint.
Miniaturization is a recent trend
in automotive components, so that when a BGA or a QFN/BTC component with low
standoff and narrow pitch is frequently soldered. Consequently, there is a
growing demand for the solder alloy composition to possess better thermal
resistance than conventional SAC305(Sn/3.0Ag/0.5Cu) solder. To answer this
demand, solid solution strengthened solder alloys which are tin (Sn) base alloys
strengthened by Bismuth (Bi) and Antimony (Sb), hereinafter SAC+Bi,Sb solder
are suggested. Although the strength is improved by these solder alloy
compositions, and better thermal resistance than SAC305 is anticipated, it is
also of concern that this composition may have different reliability reduction
than SAC305, as its properties, such as ductility and hardiness are drastically
different from SAC305.
In this paper, we will discuss the ductility and durability of a solder joint based on the shear strength test results of chip resistor soldered joints.
You have question?