Firing schedule

Figure 5. A time-temperature firing schedule of the thermal gradient furnace at the 12 thermocouple points of measurement...

Firing of Enamels. Firing can be carried out in intermittent box-type furnaces or continuous furnaces. The dryer and the furnace form one continuous unit or function as separate units in the continuous firing process. Most industrial furnaces are fiber-lined (low thermal mass), which lowers cost and downtime between firing schedules. 

The fabrication route for PTC thermistors is typical of that employed for modern electroceramics except in so far as special attention is given to maintaining high purity and to the firing schedule. 

At the end of the firing schedule, the cylindrical furnace is cooled, the quartz column is removed, and the actinide oxide microspheres are transferred by pouring into the platinum-lined crucible. The open-top crucible is placed in a muffle furnace and the oxide is sintered at about 1050°C for 16 h. Although there is no forced air flow during the sintering step, the approximately 10-mm-deep bed of oxide is exposed to air inside the furnace. After sintering has been completed, the oxide is cooled prior to the oxide characterization steps. 

Tunnel kilns are usually heated with gas or liquid fuels, and in some instances by means of electrically heated metal or SiC or M0S12 elements. The firing schedule can be controlled directly by burners and draught, and by adjusting the car speed. More uniform temperature distribution over the cross-section-is attained in small tunnel kilns which find application in the firing of special ware however, kilns with large cross-section arc used in normal ceramic operation. The functioning of a tunnel kiln is shown in Fig. I86. 

Disc-shaped green specimens were prepared by vibration-condensation method and then sintered at 930°C following the firing schedule recommended by the manufacturer. After filing, the specimens were machined and mirror-polished with diamond suspensions down to 1 pm. For each test condition at least 10 specimens (12.5 mm in diameter and 1 mm in thickness) were prepared. 

Robinson GC (1952) Limitations imposed by raw mateials on firing schedules. J Am Ctaam Soc 35 1-5... 

Datapaq Trade-name. An automatic recording system of travelling thermocouples, which can pass through e.g. a tunnel kiln and provide a record of the firing schedule. 

Firing Range. See firing temperature. Firing Schedule. The intended relationship between temperature and time during the firing of a ceramic product. 

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