Heater molybdenum disilicide
The advantages of molybdenum heaters
Molybdenum has a high heat resistance enabling a working temperature of over 2000 °C. the Heaters of this type, very durable and aggressive fluid or gaseous media are not destroyed. They are designed for long term work. Molybdenum has a high modulus of elasticity, negligible temperature coefficient of linear expansion, which gives the opportunity to apply it in the most difficult production conditions. Molybdenum in comparison to tungsten easier almost doubled, so molybdenum products have high specific strength (at a temperature of not more than 1370 °C).
Chemical properties
Molybdenum reacts with hydrochloric, sulfuric acids only at the temperature. 80−100°C. Nitric acid, Aqua Regia dissolved molybdenum only when температуре100°C. In cold alkaline solutions it is stable, but in hot alkaline solutions the molybdenum slowly being destroyed. Impurities of carbon, oxygen, silicon, aluminum, nitrogen, iron, sulfur and calcium, phosphorus, contained in the technical molybdenum in hundredths or thousandth fractions of a percent, significantly affect the properties of molybdenum. The bulk of these impurities makes molybdenum more fragile. Most harmful of all impurities is oxygen. If it is contained in a volume 0,0008−0,004%, the low-melting oxides can lead to a sharp increase in its brittleness and a decrease in properties to plastic deformation, especially in the simultaneous presence of carbon with nitrogen. With increasing percentage of oxygen than 0.015% molybdenum is not handled the pressure and becomes brittle.
| Physical properties of molybdenum | |
|---|---|
| The temperature at which the obtained data the features of t°C | 20°C |
| The linear thermal expansion coefficient α [1/°C] | 4,9x10-6 |
| Density [g/cm3] | 10,2 |
| The melting temperature t°C | 2620°C |
| Specific heat at 20 °C [kJ/(kg·deg)] | 0,256 |
| The thermal conductivity K [W/(m·K)] | 142 |
| Electrical resistivity R, Mhmm2/m | 0,054 |
Disadvantages
Practically the only disadvantage is the high cost of molybdenum heaters, since Mo is a metal belonging to rare earth elements and in its pure form is quite difficult to identify. Besides, he is refractory and hard to work.
Manufacturer
Molybdenum heaters come in all shapes and sizes. They look generally like riveted shell belt, flat spiral or cylindrical form of strips and sheets. They may have a bottom having a hole for hydrogen (the gas outlet) through the tube of the furnace space. Tolerances and dimensions match the drawings of the customers. The technology of making heaters of high quality tungsten, molybdenum-tungsten (MoW30), or molybdenum is guaranteed operational reliability and the absolute refractoriness. Price heaters depends on the complexity of the configuration, dimensions and additional requirements that are specified in the order.
Use
Molybdenum heaters are part of the structures of the hydrogen and vacuum electric resistance furnaces, and induction furnaces sintering furnace, whose working temperature is over 2000 °C. These heaters are indispensable for melting sapphire and glass, growing single crystals, sintering of powder products, etc.
Buy at best price
Huge selection of molybdenum heaters in stock LLC «AVEK global» can satisfy any customer. Absolute compliance with all technological norms of production ensures the quality of the finished product. Deadlines all orders the shortest possible. For any questions, experienced managers will give a full detailed advice. Carrying out wholesale orders, you can count on company-provided flexible system of discounts.