Method and apparatus for dynamic nitriding

Abstract

A nitriding method includes the steps of nitriding an object held under a nitriding gas atmosphere in a sealed furnace and applying vibration energy to one or both of the nitriding gas and the object W to facilitate nitriding. A nitriding apparatus includes a nitriding furnace for holding an object W to be nitrided in a sealed manner, means 30 for supplying a nitriding gas to the furnace, and means 2 for applying vibration to the atmosphere gas in the furnace 1 to faciliate nitriding. According to the method or apparatus, nitriding-resistant or complex-shaped materials can be nitrided at high efficiency and a nitrided layer can be formed at a lower temperature for a shorter time as compared with conventional processes.

1 . A method for dynamically nitriding an object, comprising the steps of: 
 nitriding said object held under a nitriding gas atmosphere in a sealed furnace; and    applying vibration energy to one or both of said nitriding gas and said object to facilitate nitriding.    
     
     
         2 . The method according to claims  1 , wherein said vibration energy is so selected as to generate vibration at a vibration frequency of 400 to 5000 vibrations per minute.  
     
     
         3 . A gas vibration type nitriding apparatus, comprising: 
 a nitriding furnace for holding an object to be nitrided in a sealed manner; means for supplying a nitriding gas to said nitriding furnace; and    means for applying vibration to an atmosphere gas in said nitriding furnace, 
 wherein nitriding will be facilitated by allowing said atmosphere gas to vibrate.  
   
     
     
         4 . A gas vibration type nitriding apparatus, comprising: 
 a nitriding furnace for holding an object to be nitrided in a sealed manner;    gas supply lines for supplying a nitriding gas and/or one or more atmosphere gases other than said nitriding gas to said nitriding furnace; and    means for applying vibration to one or more gases in some or all of said gas supply lines, 
 wherein nitriding will be facilitated by atmosphere gas vibration.  
   
     
     
         5 . The gas vibration type nitriding apparatus according to  claim 3  or  4 , wherein said means for applying vibration is a fast vibrating diaphragm, and one or more gases being supplied to said furnace are allowed to collide against said vibrating diaphragm to apply vibration to atmosphere gas in said furnace.