There has been major interest in Lead-free soldering within the electronics assembly industry for the last several years, and this will continue with the agreement on the language and implementation dates of the WEEE/ROHS legislation in the EU. This paper will focus on several topics critical to the implementation of lead-free soldering. These topics include the impact of Tin-silver-copper as t...

The structural and conducting properties of single-wall carbon nanotubes SWCNs in soldered configuration is obtained using efficient formalisms based on spin-polarized tight-binding formulation incorporating full consideration of s, p, and d basis sets for carbon and metal atoms. The full structural relaxation of the combined SWCN and metal system is found to be essential for realistic characte...

early 40 years of experience with wave soldering N have resulted in processes that routinely produce several thousand, defect-free solder joints per minute. However, the climate of electronics manufacturing has changed significantly over the past 10 to 15 years. Environmental restrictions as well as the high quality of products made offshore has placed new demands and challenges on the electron...

In this study, we have investigated the effect of thermal aging on impact strength of Sn-Ag-Cu solder bumps in fluxless soldering process using formic acid atmosphere. We conducted impact tests on as-reflowed and thermally-aged solder bumps, which were fabricated on either formic acid atmosphere or a liquid flux. The results indicated that the morphology of the intermetallic compound layers in ...

“Sagging” of the palatal cusp upper second molars is a common finding observed during orthodontic treatment which may develop heavy balancing side contacts, have been found to be detrimental harmonious function masticatory system. Various modifications transpalatal arch (TPA) are advocated correct crossbite, but most them will utilize an additional step soldering wire attachment TPA. In this cl...

The article describes a mathematical model of temperature changes in the soldering iron an automated installation used terminal glass heating system created for automotive manufacturers. effect changing shape welding machine on distribution has been studied. results were compared with experimental data

We show that the recently developed soldering formalism in the Lagrangian approach and canonical transformations in the Hamiltonian approach are complementary. The examples of gauged chiral bosons in two dimensions and self-dual models in three dimensions are discussed in details.