Advanced gas quenching techniques in the vacuum heat-treating process for superior coining die performance involve optimizing the micro-structure of the die surface to provide uniform hardness and minimizing distortion.
An excerpt:
“The minting industry has to be compliant to the highest level of standard certifications in order to avoid every possibility of falsification and, at the same time, to satisfy a high level of quality and reproducibility. The quantity of money and the great variety of coins in the world means that it is essential not to make any sort of mistake in all the minting processes. In the first part of this article, we’ll take an interesting step-by-step look at the minting process, while in the second part we’ll discover the most optimized heat treatments for the minting industry.”
Source: TAV Vacuum Furnaces