PLASMA ION NITRIDING
Plasma ION nitriding is an industrial surface hardening treatment for iron-based materials. It is the most technically superior of all nitriding processes and has many advantages compared to traditional salt bath and gas nitriding.
A plasma nitrided part is usually ready for use directly after treatment requiring no machining, polishing or any other post-nitriding finishing operations. The process is eco-friendly, saves energy and causes little or no distortion.
This process permits the close control of the nitrided microstructure, allowing nitriding with or without compound layer (white layer) formation. In addition to enhanced material performance, the lifespan of your parts will increase with much improved strain limits, fatigue strength, wear resistance and corrosion protection.
It is a case hardening treatment performed in a mixture of nitrogen and hydrogen with small additions of gases containing carbon. In this process a high voltage electrical charge forms plasma, causing nitrogen ions to accelerate and impinge on the applicable material. When the nitrogen ions bombard the part, they heat up the metal, clean the surface and diffuse nitrogen into the surface. It extends part/tool life. It adds performance, fatigue strength and endurance. It enhances surface lubricity and reduces erosion. It increases material flow in molds and dies. It helps in selective hardening processes.
The Plasma Ion process is done in a vacuum vessel at low temperatures (750°-1040°F or 400°-560°C) where high-voltage electrical charge forms plasma, causing nitrogen ions to accelerate and impinge on the metal. When the nitrogen ions bombard the part they heat up metal, clean the surface, and absorb nitrogen into the surface, and can be applied to any ferrous metal.
Benefits of Plasma Ion Nitriding
- Extends part/tool life
- Selective hardening process
- Reusable masking (versus coatings or other surface treatments)
- Adds performance, fatigue strength and endurance
- Enhances surface lubricity
- Reduces erosion
- Increases liquid material flow in molds and dies
- Improves corrosion resistance
- No post-process machining required
- Improves wear resistance
- Zero to minimal growth/distortion
- Precise and versatile
- Environmentally friendly process (i.e. free of toxic salts, ammonia and any other toxic gases)
- Phase controllable compound zone (or white layer)
- Less distortions than gas nitriding because plasma nitriding is performed at a lower temperature and under a vacuum.
- Higher surface, case, and core hardness than gas nitriding.
- Excellent wear resistance: the plasma ion nitriding process produces a compound zone that is dense, nonporous, very hard but not brittle, and has a low coefficient of friction.
- Reproducible results and better control compared to gas nitriding: the process of plasma nitriding is fully automated and computer controlled.
- Great surface finish: no additional mechanical treatments are necessary.
- Easy masking: surfaces requiring selective treatment are easily masked with reusable mechanical masking devices that are 100% effective.
- Excellent hygiene and working conditions: the process is non-toxic and abides by all modern environmental control standards.
- Low to high alloyed steels and stainless
- It produces a compact, dense and more “ductile” compound layers than other nitriding processes
- Improved surface finish and much cleaner surfaces as compared to salt bath and gas nitriding
- Possibility of re-oxidization (post nitriding corrosion protection).
- Components and tools with plasma nitrided surface have an enhanced resistance to wear and crack formation, improved frictional, and sliding properties and higher fatigue strength values.
Applications:
- Dies and punches for metal forming
- Gears
- Crank shafts
- Feed screws
- Camshafts
- Guides
- Cylinders
- Mandrels
- Molds for plastics
- Molds for casting of nonferrous metals and alloys
- Milling tools
- Drilling tools