Coppersmith extensive degree it must be annealed. This process involves heating the metal and then rapidly cooling it in water. The cooling stage is known as quenching. By heating the copper, the molecules in the metal are relaxed, and thus able to align themselves in a more uniform fashion. This allows for easier shaping of the metal. In order to keep this uniformity within the metal, it is cooled instantly. This prevents the molecules from moving around and causing tension in the structure of the metal. Unlike ferrous metals—which must be cooled slowly to anneal—copper can be cooled slowly in air
Glass-to-metal seal case that the CTE of the metal is larger than the CTE of the glass, the sealing shows a high probability to break upon cooling. By lowering the temperature, the metal wire shrinks more than the glass does, leading to a strong tensile force on the glass, which finally lead to breakage. On the other hand, if the CTE of the glass is larger than the CTE of the metal wire, the seal will tighten upon cooling since compression force is applied on the glass. According to all requirements that need to be fulfilled and the strong necessity to align