In this study, we investigated the microstructure, mechanical properties, and thermal performance of Sn-xBi-1Ag (x = 35, 37, 45, 47 wt.%) solders, with a particular focus on effect adding trace Si atoms. The impact different Ag concentrations properties Sn-xBi-Ag-0.5Si solders was also studied. results indicated that as amount Bi added to solder alloys increased, tensile strength, microhardness...

With the upcoming European ROHS legislation and other global movements to lead-free assembly, the NEMI lead-free rework group investigated and developed lead-free rework processes for medium to high-end computer products. The work concentrated on development of lead-free hot air convection rework for PBGA, CBGA, and uBGA, and lead-free hand soldering rework for TSOP and 2512 chip components on ...

The waveguides used in spacecraft antenna feeders are often assembled using external couplers or flanges subject to further welding soldering. Making permanent joints by means of induction heating has proven be the best solution this context. However, several physical phenomena observed zone complicate any effort control process making a joint heating; these include flux evaporation and changes...

The processes of melt formation were studied by methods optical and electron scanning microscopy. These occur during induction brazing a hard alloy to steel holder contact interaction low-melting (copper-zinc system alloy) refractory (iron-nickel) components the solders. It is shown that effect thermal magnetic-dynamic high-frequency electromagnetic field on composite solder how high-strength j...

We start this work by revisiting the problem of the soldering of two chiral Schwinger models of opposite chiralities. We verify that, in contrast with what one can conclude from the soldering literature, the usual sum of these models is, in fact, gauge invariant and corresponds to a composite model, where the component models are the vector and axial Schwinger models. As a consequence, we reint...