What is used in refractory crucibles?
Crucibles and their covers are made of high temperature-resistant materials, usually porcelain, alumina or an inert metal. One of the earliest uses of platinum was to make crucibles. Ceramics such as alumina, zirconia, and especially magnesia will tolerate the highest temperatures.
What are crucibles used for?
Used from ancient times as a container for melting or testing metals, crucibles were probably so named from the Latin word crux, “cross” or “trial.” Modern crucibles may be small laboratory utensils for conducting high-temperature chemical reactions and analyses or large industrial vessels for melting and calcining …
Why are crucibles made of graphite?
Electric Resistance Furnace Crucibles have to have a high graphite content in the carbon binder for energy savings and high thermal conductivity. They are basin shaped and are placed at equal distance from the heating elements.
What is the main purpose of crucible tongs?
Crucible tongs are scissor-like tools, but instead of having two blades, these tools are replaced with two pincers or pieces of metals that concave together, which allow the users to grasp a hot crucible, flasks, evaporating dishes, or even small beakers.
What are graphite crucibles?
A graphite crucible is a container used for melting and casting non-ferrous, non-iron metals such as gold, silver, aluminum, and brass. This form of graphite is manufactured by combining graphite with fire resistant clay or carbon dioxide.
What are the different types of crucibles?
Porcelain, PTFE, Stainless Steel, Nickel, Carbon Steel, Zirconium and Vitreous Carbon
| Porcelain Crucibles | Platinum Crucibles | PTFE Crucibles |
|---|---|---|
| Stainless Steel Crucibles | Nickel Crucibles | Carbon Steel Crucibles |
| Zirconium Crucibles | Vitreous Carbon Crucibles | Crucible Tongs |
What are scientific tongs?
Laboratory tongs are large pincers for grasping and lifting vessels of heat-resistant material used in high temperature chemical reactions. Tongs differ in shape are designed to pick up laboratory items including, hot evaporating dishes, beakers, crucibles, and other laboratory apparatuses.