Use of high purity cyclic napthene hydrocarbon and precision controlled liquid injection delivery system yields repeatable, high-quality results over a wide range of vacuum carburizing process variables.
A new vacuum carburizing technology, which will be commercially known as VringCarb, has been introduced by Surface Combustion Inc. The process is performed at low pressure in a vacuum furnace using a high-purity napthene hydrocarbon as the carburizing compound. The furnace is designed to be inert with respect to the napthene so cracking of the gas occurs only at the workpiece, minimizing carbon deposits. The napthene is supplied in liquid form to fuel injectors that convert the carburizing medium to a vapor, producing a vapor dispersion around the work, which results in uniform carburizing. Patent applications for the technology were filed in July 2002. Background material on the chemistry involved, purity, delivery, control, process results and furnace design and configurations are presented in this article. Future articles will explore further process results and expand on the tremendous potential of this new processing approach and technology.