Magnesium alloy, copper and other light alloys are widely used in aerospace, new energy vehicles, lightweight manufacturing fields due to their excellent mechanical properties, but the connection between has always been a challenge. Ultrasonic welding is an advanced technology that can realize high-strength heterogeneous alloys. In this study, ultrasonic AZ31B magnesium pure carried out. The fr...

The lifetime of the solder joint between base plate and ceramic substrate is usually tested by passively heating and cooling the IGBT module (thermal cycling). This provokes failures (delamination) in that solder layer. But, the IGBT and diode dies are actively heated in the application. Other failure modes (e.g. bond wire lift off) are addressed and limit the lifetime. This kind of stress is u...

Experiments using eutectic Sn–3.5% Ag solder paste were conducted with the objective of examining the conjoint influence of copper particles addition and rapid cooling on microstructural development. The composite solder mixture was made by thoroughly mixing a pre-weighed amount of copper particles with a commercial Sn–3.5% Ag solder paste. The experiments were quite similar to the heating and ...

The microstructure, mechanical response, and failure behavior of lead free solder joints in electronic assemblies are constantly evolving when exposed to isothermal aging and/or thermal cycling environments. In our prior work on aging effects, we have demonstrated that the observed material behavior variations of Sn-Ag-Cu (SAC) lead free solders during room temperature aging (25 C) and elevated...

The kinetics of the solid-state reactive diffusion between Sn­Ni alloys and pure Cu was experimentally observed to examine effects of addition of Ni into Sn on the growth behavior of compounds at the interconnection between the Sn-base solder and the multilayer Au/Ni/Cu conductor during energization heating. In this experiment, sandwich (Sn­Ni)/Cu/(Sn­Ni) diffusion couples with Ni concentration...

Cu-based alloys are one of the most promising substrates to enhance performance lead-frame materials. In present study, interfacial reactions in Sn-0.7 wt.% Cu (SC) lead-free solder reacting with Cu-3.3 Fe (C194), Cu-2.0 Be (Alloy 25), and Ti (C1990 HP) were investigated. The material underwent a liquid–solid interface reaction, reaction time was 0.5 few hours at temperatures 240 °C, 255 270 °C...

The influences of Er content on the interfacial microstructure shear properties and creep Sn58Bi joints were investigated in this study. intermetallic compound composition Sn58Bi-xEr/Cu was Cu6Sn5 compound. addition suppressed activity Sn element, decreased driving force for growth thickness layer. durability welded improved to a certain extent. At 0.1%, strength solder alloy are relatively opt...

A novel and direct method to measure the stress-strain properties of surface mount solder joints is proposed in this paper. The specimen used in the experiments is a quad flat pack (QFP)-solder-printed circuit board (PCB) assembly and the fabrication of solder joints makes use of conventional surface mount technology (SMT). Mechanical cycling and thermal shock testing can be conducted directly ...

One of major reasons of failure of solder joints is known as the thermal fatigue. Also, The failure of the solder joints under the thermal fatigue loading is influenced by varying boundary conditions such as the material of solder joint, the materials of substrates(related the difference in CTE), the height of solder, the Distance of the solder joint from the Neutral Point (DNP), the temperatur...