The oxide layer is extremely thin, typically up to about https://www.surrey.ac.uk/mes/files/Castle_paper2.pdf. For such thin layers, the breakdown voltage is well within the voltage range that a multimeter can reach (for example a breakdown voltage of 6V is reported http://photonics-benelux.org/proc08/s08p195.pdf for a 10nm crystalline sample)spareine said:Aluminium surfaces are protected by a thin aluminium oxide layer. The oxide layer supposedly does not conduct electricity. However, when measuring the contact resistance between the test pen of a multimeter and the aluminium, this resistance is always small. Why? Is the oxide layer easily punctured?
What is the smallest current range on your multimeter?spareine said:Aluminium surfaces are protected by a thin aluminium oxide layer. The oxide layer supposedly does not conduct electricity. However, when measuring the contact resistance between the test pen of a multimeter and the aluminium, this resistance is always small. Why? Is the oxide layer easily punctured?
Aluminium oxide is a compound composed of aluminium and oxygen atoms. It forms on the surface of aluminium when the metal is exposed to oxygen in the air. This process is known as oxidation, and it creates a thin layer of aluminium oxide on the surface of the metal.
The presence of aluminium oxide on a surface can significantly decrease its conductivity. This is because aluminium oxide is an insulating material, meaning it does not allow the flow of electricity. The layer of aluminium oxide can act as a barrier to the flow of electrons, reducing the conductivity of the surface.
Yes, the conductivity of an aluminium oxide surface can be improved by removing the layer of oxide. This can be done through processes such as sanding, polishing, or using chemical treatments. By removing the layer of insulating aluminium oxide, the surface's conductivity can be increased.
The thickness of aluminium oxide can have a significant impact on the surface's conductivity. Thinner layers of oxide will have a lower impact on conductivity compared to thicker layers. This is because a thicker layer of oxide creates a larger barrier for the flow of electrons, resulting in lower conductivity.
The formation and thickness of aluminium oxide on a surface can be influenced by various factors. These include the exposure to oxygen, temperature, humidity, and the presence of other chemicals. These factors can affect the rate at which oxidation occurs, leading to varying thicknesses of aluminium oxide on a surface.