Abstract
Vacuum tempering has long been recognized for ensuring part cleanliness and brightness, but recent technological advancements significantly improve processing efficiency. By increasing the operating pressure to 2 bar absolute, new vacuum furnace designs dramatically reduce heating and cooling times while maintaining the traditional benefits of vacuum-purged tempering. The process involves an initial evacuation, backfilling with an inert gas, and utilizing convection heating, with the increased gas pressure enabling higher molecular density and more rapid thermal transfer. Additional innovations, such as hot wall technology and potential future developments like inside/out insulation, promise to further enhance energy efficiency, reduce operating costs, and address challenges associated with higher pressure systems. Test results confirm substantial improvements in heating and cooling rates, presenting a promising approach to optimizing heat treatment processes for ferrous and nonferrous components.
