1. NITRIDING
Brett Iseneker

2. History of nitriding
Dr. Adolph Fry in the 1900s Figured out that iron and nitrogen had an attraction to each other 1906 he developed the iron-nitrogen equilibrium diagram The process was discovered around the same time in the United States and Germany but wasn’t used much until after world war 2

3. Heat is applied to both iron and a nitrogen gas
The nitrogen will diffuse into the surface of the steel and create a change in the surface of the steel
This gas nitriding process will harden the steel

4. What metals is nitriding used on?
Aluminum
Steel
Titanium
Molybdenum

5. BENEFITS OF NITRIDING Higher surface hardness Increase wear resistance
Improve fatigue life
Improve corrosion resistance (except for stainless steels)
Stop metals from softening when being heated

6. Benefits
Reduced cylinder wall wear - the harder a surface the more difficult to wear down
Improved piston ring life from a straight cylinder wall when engine is hot, and a better job of sealing
Nitriding allows use of chrome plated piston rings, which are more wear resistant and will work with hardened steel
Increase tensile strength

7. Gas Nitriding process
Nitrogen into the surface layers of alloy steel of almost finished parts to an atmosphere of ammonia gas
Requires special heat treating furnaces which are air tight and can hold the parts at a high temp
At 975 degrees, the ammonia gas flowing into the furnace is broken down into elements of hydrogen and nitrogen
Nitrogen will enter the surfaces of the steel. The process takes hours

8. Different types of nitriding
Gas Nitriding ( explained above) Salt Bath Nitriding- uses nitrogen that has cyanide salt, the salts give carbon to the part being nitrided and gives it a nitrocarburizing process. Temperatures are around 1022–1094 degrees F. This can be done in 4 hours so it is much quicker than gas nitriding Plasma Nitriding-Doesn’t react because of heat but because of the gas in ionized state. electric fields are used to make ionized molecules of the gas around the part or surface to be nitrided. Highly active gas with ionized molecules is called plasma. The gas used for plasma nitriding is usually pure nitrogen

9. Disadvantages of each process
Gas nitriding -Any dirt or oil on the surface of the metal being treated will not come out right. Has to be prepped carefully. Ammonia as a nitriding is toxic if inhaled
Plasma nitriding- more costly than other ones
Salt bath nitriding- salts used are highly toxic

10. Nitriding Problems

11. Commonly nitrided parts
Gears
Crankshafts
Camshafts Valves
Cylinders

12. Tooling
Landing gear parts
Shafts that are exposed to weather
Stainless Steel shafts
Piston rings
Springs
Fuel injectors

13. Gas Nitriding furnace