|
bgiorgi
New Member
USA
1 Posts |
 Posted - Dec 04 2014 : 08:32:45 AM
|
| The mechanics of soldering is a topic which I have pondered for many years. I have a degree in electronics engineering and have spent many hours on the cool end of a soldering iron. Everything that I have been taught tells me that in the soldering process, an alloy layer is created at the junction but my studies in metallurgy tell me different. In order to create a metal alloy, both metals must be taken to their molten state either before or while being combined. A soldering iron’s temperature generally runs between 700-850 Deg. F. which is not enough to bring copper to its molten state which happens at 1,984 Deg. F. If soldering was a process of creating an alloy, why can’t aluminum be soldered? Copper has a melting point of 1,984 Deg. F. and we can create an “Alloy”, why can’t we create an alloy with Aluminum whose melting point is just over 1,200 Degrees F.? Ponder this and let me know what your thoughts are. Here is what I think happens during the soldering process…… As the copper substrate is heated, its granular structure (Pores) opens up, the solder then fills the voids of the coppers granular structure. As the copper cools, the granular structure closes onto the solder which creates an interlocked lattice and the bond is created. Because there is no air in the joint due to a vacuum being created as the joint cools, no oxidation will take place at the actual connection. Aluminum cannot be soldered because its granular structure is much smaller than that of copper. Because it is so small, the solder cannot flow into the voids to make the bond. |
|
Soldering
