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Solder joints provide both electrical and mechanical interconnections between a silicon chip and the packaging substrate in an electronic application. The thermomechanical cycling in the solder causes numerous reliability challenges, mostly because of the mismatch of the coefficient of thermal expansion between the silicon chip and the substrate. The actual transition to lead-free solders and the trend towards hotter-running, miniaturized and higher current density chips aggravate this situation. Therefore, improved solder joints, with higher resistance to creep and low cycle fatigue, are necessary for future generations of microelectronics. This study focuses on a thermomechanical behavior comparison between monolithic Sn-Ag-Cu, copper fiber and copper ribbon cylindrical reinforced solders. The composite solders were found to reduce the inelastic strain range of the joint relative to monolithic solder, but at the expense of increased stress range.

Solder joints provide both electrical and mechanical interconnections between a silicon chip and the packaging substrate in an electronic application. The thermomechanical cycling in the solder causes numerous reliability challenges, mostly because of the mismatch of the coefficient of thermal expansion between the silicon chip and the substrate. The actual transition to lead-free solders and the trend towards hotter-running, miniaturized and higher current density chips aggravate this situation. Therefore, improved solder joints, with higher resistance to creep and low cycle fatigue, are necessary for future generations of microelectronics. This study focuses on a thermomechanical behavior comparison between monolithic Sn-Ag-Cu, copper fiber and copper ribbon cylindrical reinforced solders. The composite solders were found to reduce the inelastic strain range of the joint relative to monolithic solder, but at the expense of increased stress range., http://archive.org/details/thermomechanical109452062, Approved for public release; distribution is unlimited.

Solder joints provide both electrical and mechanical interconnections between a silicon chip and the packaging substrate in an electronic application. The thermomechanical cycling in the solder causes numerous reliability challenges, mostly because of the mismatch of the coefficient of thermal expansion between the silicon chip and the substrate. The actual transition to lead-free solders and the trend towards hotter-running, miniaturized and higher current density chips aggravate this situation. Therefore, improved solder joints, with higher resistance to creep and low cycle fatigue, are necessary for future generations of microelectronics. This study focuses on a thermomechanical behavior comparison between monolithic Sn-Ag-Cu, copper fiber and copper ribbon cylindrical reinforced solders. The composite solders were found to reduce the inelastic strain range of the joint relative to monolithic solder, but at the expense of increased stress range.

The current notion of seabasing requires that three Battalion Landing Teams (BLT) of a 2025 Joint Expeditionary Brigade (JEB) need to be able to transit from the Sea Base to the objective within a 10 hour period. Of the three BLTs, two of them must be transported by surface craft a distance of no more than 200nm in sea state 4 or less. The two surface bound BLTs need to be loaded onto the transporting craft and delivered to shore, whether it is a port facility or austere beachhead. There is no current or future system of connectors to meet all the time-distance, sea state, and interface flexibility requirements for this aspect of seabasing. To meet these requirements a High Speed Assault Connector (HSAC) is needed which either augments current or replaces existing connector platforms to deliver and support the required forces ashore. The Joint ACCESS is a HSAC that brings the necessary speed, payload capacity, interface capability, and mission flexibility needed to fill the Sea Base to shore transportation gap. With a maximum speed of 43kts and payload capacity of 800LT, 12 Joint ACCESS trimarans can transit 200nm and fully offload in 7 hours. Its beachable design uses a floating bow ramp to reach out to austere beaches, while its combat system suite provides self defense in addition to robust offensive capabilities.