That is why the silicon molybdenum has the unique high-temperature oxidation resistance. During oxidation atmosphere, the maximum using temperature is 1800℃, Based on the user's require it can be made of bar-shaped, U, W, U right angles, and other shapes. Silicon molybdenum rods usually can be used at the furnace which temperature range is around 1300 ℃ to 1800 ℃, It is widely used in metallurgy, glass, ceramics, magnetic materials, refractory materials, crystal, electronic components, kiln manufacturing, and other fields. It is the ideal heating element for high-temperature sintering.
Physical properties of silicon molybdenum rod:
Bulk Density
Flexural strength
Vickers hardness
Porosity
Bibulous rate
Heat extensibility
5.5 g/cm3
15-25 kg/cm3
(HV)570kg/mm2
7.4%
1.2%
4%
Chemical properties of silicon molybdenum rod:
High temperature using under the oxidizing atmosphere, the surface will be vitrifying, producing a bright and compact quartz (SiO2) glass film, it can protect the silicon molybdenum no longer oxidation. When the element temperature is above 1700℃, The quartz protection layer melts. Continue to use, the quartz protection layer is regenerated. Silicon molybdenum rods should not be used under the temperature range of 400-700℃ for a long time, Under a low-temperature environment, the element will pulverize due to strong oxidation.
Silicon molybdenum rod working Temperature changing during different atmosphere
Atmosphere
Element Maximum Using Temperature
Model 1700
Model 1800
NO2, CO2, O2, Air
1700℃
1800℃
He, Ar, Ne
1650℃
1750℃
SO2
1600℃
CO, N2
1500℃
Wet H2
1400℃
Dry H2
1350℃
1450℃
The Electric Appliance Performance Of Silicon Molybdenum Rod
The resistivity of an element rapidly rises as the temperature rises, under normal operating conditions, generally, the element resistance doesn't change with the service time changing, So old and new components can be mixed.
The Load Of Silicon Molybdenum Rod Surface
Based on the furnace structure、atmosphere and temperature to choice a load of the right element is the key point to let the element to reach the maximum lifetime, as the picture shown below shows the relationship between the temperature of the furnace, the temperature of the element and the surface load in the unhindered condition of the heating element. The shadow part is the common surface load - the temperature range.
Installation of silicon carbide rod
Silicon molybdenum rods it has brittleness at normal temperature and it has plasticity at high temperature. That is why the U type silicon molybdenum rod is better to choose the vertical installation, If the element requires horizontal installation, then need using refractory materials to support the element, horizontal setting the silicon molybdenum rod, the conical part of the element must extend inside the furnace hearth, silicon molybdenum rod clip cannot be once screwed too tight, until the element reaches to high temperature, tighten up again, Then the element cannot easily break off.(Suggestion: Please select the special clips and wires equipped from our company ), furnace top needs better heat preservation performance, usually, the temperature cannot beyond 300℃,The contact voltage between the clip and the element be less than 0.1v, To avoid heat transfer to the clip, the distance of clip bottom and plug brick top need above 50mm. a φ6 element cannot long-term using 170A,φ9 element cannot long-term using 300A。
Newly built or long-unused furnaces need to be dried before use, The drying temperature is 100-200℃.
Large furnace drying time is long, it is best to use other heating element oven, lest the silicon molybdenum rod low-temperature oxidation, the furnace drying, can follow the following steps to start heating up.
Miniature furnace (Rated power < 100KW)
Large-scale furnace (Power 100-500KW)
Furnace Temperature (℃)
Voltage(v)
Furnace Temperature(℃)
20-150
1/3 Working Power
20-300
150-500
2/3 Working Power
300-700
500-Working Temperature
Full working voltage
700- Working Temperature
YH-XAD
YH-GA
YH-XZGA
YH-XB
YH-LB
YH-KQGA