Plasma Carburizing
Plasma Carburizing Technology
In plasma carburizing, the workpiece is first heated to carburizing temperature inside a vacuum furnace using an external heater. Then, the furnace wall and thermal insulation material are set as the anode, while the workpiece acts as the cathode. A hydrocarbon-based gas atmosphere—typically methane or propane—is maintained at 2–3 Torr, and a direct current voltage of several hundred volts is applied to generate a glow discharge.
Within the resulting plasma, electrochemical interactions cause the hydrocarbon ions to bombard and diffuse into the workpiece surface, initiating the carburizing reaction.
While heating is primarily provided by the external heater, the plasma also activates and cleans the surface, enhancing treatment effectiveness—features not possible with conventional carburizing methods.
Plasma Carburizing Equipment
The plasma carburizing system combines thermal energy with the electrochemical action of DC glow discharge plasma to form a hardened carbide layer on metal surfaces, enhancing mechanical strength. As industries face increasing demands for energy conservation, material efficiency, and electronic integration, expectations for component quality have risen dramatically.
There is a growing need for high-performance, high-precision heat treatment.
NDK’s plasma carburizing technology meets these demands by providing clean processing conditions, high treatment efficiency, and stable quality output.
It also enables high-concentration carburizing and treatment of difficult-to-carburize materials (such as stainless steels and sintered alloys), opening new possibilities beyond the limits of traditional methods.
Key Advantages of Plasma Carburizing
Clean, Glossy Surface with No Intergranular Oxidation : Produces a bright, clean surface without intergranular oxidation—ideal for applications requiring aesthetic or functional surface quality.
Uniform Carburizing at Low Pressure : Plasma-assisted process allows uniform carburizing even at low pressure, without soot formation (unlike gas or vacuum carburizing).
Fast, Low-Temperature Treatment with No Grain Growth : Enables rapid carburizing at low temperatures, minimizing grain growth and preserving core mechanical properties.
Deep Carburizing for Difficult Materials : Supports high-concentration carburizing, even for materials traditionally difficult to treat (e.g., stainless steel and sintered alloys).
Eco-Friendly and Energy-Efficient : Environmentally clean process with minimal gas usage, contributing to energy savings and workplace safety.