Achieving high quality bright nitriding
■1.Nitriding overview
Nitriding is used industrially in various fields such as automobile and aircraft parts, jigs, tools, and molds for the purpose of improving mechanical properties such as hardness and wear resistance. In particular, nitriding using plasma can be performed below the tempering temperature (500°C), causing less thermal deformation and less surface roughness, so it is used as a base treatment for molds, sliding parts, and coatings. is increasing.
Active screen plasma (ASP) nitriding is a hybrid nitriding technology that combines both bright nitriding that maintains specularity and conventional ion nitriding by adjusting the bias voltage applied to the processed product.
■2. Equipment
<ASP nitriding equipment configuration>
The ASP nitriding method is characterized by installing a screen between the processed product and the furnace wall, using the screen as a cathode and the furnace wall as an anode, and generating plasma between the screen and the furnace wall. Plasma containing a mixture of nitrogen ions and radicals is formed on the surface of the screen, and these plasmas reach the surface of the product to be processed, and the nitrogen is diffused into the steel material, thereby nitriding the product.
Additionally, by installing an auxiliary heater and a cooling mechanism (fan, blower), the heating time and cooling time can be shortened, making it possible to process two batches a day.
■3.Advantages
The ASP method is divided into "screen voltage" which is required for plasma generation and temperature rise, and "bias voltage" which controls nitriding performance. By adjusting the bias voltage applied to this stage side, the amount of nitrogen ions supplied to the processed product can be controlled, and hybrid nitriding can be achieved because the controllability of nitriding performance is superior to conventional methods. The ASP method performs nitriding using only nitrogen gas and hydrogen gas, so no harmful gases are used.
The ASP method does not generate plasma directly on the product to be processed, but instead generates plasma indirectly through a screen, so it is not affected by the shape of the product. Therefore, edge effects, hollow cathode effects, and arcing can be suppressed.
■4.Nitriding performance
ASP nitriding ~Hybrid nitriding~
・ASP nitriding is a hybrid nitriding that combines both high-quality bright nitriding and conventional ion nitriding.
・ASP nitriding can be performed according to the customer's required characteristics.
