Carbonitriding Furnaces for Heat Treatment by Therelek
Carbonitriding is a gaseous process for the simultaneous diffusion of carbon and nitrogen into steel and consists of subjecting steel parts to the action of a carburizing gas to which is added a nitriding gas, usually anhydrous ammonia. Carbonitriding is carried out over the range 800°C to 900°C with a preference for 850°C – 900°C.
The duration of treatment for a given case depth is a function largely of temperature, provided that a suitable gaseous atmosphere is employed. Furnaces used for carbonitriding are generally of the continuous type such as shaker hearth furnace, rotary drum furnace since the work is nearly always directly quenched in oil from the carbonitriding atmosphere.
Batch type furnaces of the standard type used for gas carburizing may also be employed, particularly where the parts in question are not suitable for rotary drum or shaker hearth furnaces.
Carbonitriding is an ideal process for the hardening of small components, where great resistance to wear is required and generally operating where the case depth does not exceed 0.025” – 0.030”
Advantages of Carbonitriding
- The process is safe, clean and simple to operate – no salts to handle no washing off, and the process can be operated by unskilled labour.
- The process is applicable to mass production methods.
- Reduced distortion due to the lower temperature required for carbonitriding as compared with carburizing, distortion is reduced.
- Improved hardenability is obtained using plain carbon steels instead of alloy steels, doe to the introduction of nitrogen into the case.
Carbonitriding Furnaces by Therelek
Sealed Quench Furnace
Therelek’s Sealed Quench Furnace line consists of preheating and tempering furnaces, washing machines, stationary table, hydraulic lifts and charge transfer systems
Chamber Furnace
Therelek’s chamber furnace can operate up to 1800°C. These furnaces are usually rugged, refractory based construction
Pit Type High Temperature Furnace
Pit type sealed retort furnaces are of a cylindrical design vertically erected with a positive sealing mechanism on top in order to contain and preserve heat and atmosphere during a process cycle.
