Objective
A furnace chamber was designed, built and installed, equipped with the plasma carburizing process and the gas quenching. Plasmagenerator, interface and electrical control as well as the safety installations, the gas supply and gas outlet were developed and installed respecting the requirements for the use of hydrogen at high pressures.
Investigations of model and industrial steel parts revealed the relationship of carburizing depth and the plasma parameters as well as quenching gas, gas pressure and heat transfer coefficients in the newly built system.
Results showed that quenching rates as high as those achieved by oil can be obtained. With these quenching rates the gas quenching process is no longer limited to high alloyed steels. The merits of the new process can be fully exploited by the European heat treatment industry keeping their competitive edge. Main advantages are:
Avoiding oil waste
Less energy consumption
Reduction of production time
Less dimensional alterations and distortions.
These advantages have to be seen in relationship to considerable higher costs for the use of hydrogen as quenching gas and higher investment costs for the vacuum heat treatment furnace with high pressure gas quenching.