What Is the Microflat in Cone-Shaped Lanthanum Hexaboride Cathodes?

[PCLNuclear]

Hi everyone.

I have studied Lanthanum Hexaboride (LaB6) cathodes the last few days, but I have a few questions regarding them. There are two types of these cathodes; the flat one and one which is in the shape of a cone. I have attached two documents which handles about these two types of cathodes.

When they are referring to the complete flat of the flat cathode, I know it is the diameter of the cylinder. In this case it is 1.78 mm (LaB6_cathode_ES440). But when they refer to the cone shaped cathodes they refer to the microflat. My question is, is this the point of the cathode to which they are referring? As I understand the microflat is the top of the cone, but in one of the documents I have attached (LaB6_cathode_ES423), they refer to the roundness and smoothness of microflat. Aren't the point then supposed to be flat?

Thanks in advance for the help!

Kind regards,
Lourie

 

[eljose79]

Hi Lourie,

Thank you for your post and for sharing your questions about LaB6 cathodes. I understand your confusion about the terminology used to describe the flat and cone-shaped cathodes. The microflat is indeed the top of the cone, but it is important to note that it is not a perfectly flat surface. The term "flat" in this context refers to the overall shape of the cathode, which is cylindrical for the flat cathode and conical for the cone-shaped cathode.

In the document you attached (LaB6_cathode_ES423), the roundness and smoothness of the microflat are important characteristics because they affect the emission of electrons from the cathode. The smoother and rounder the microflat, the more uniform and efficient the electron emission will be.

I hope this helps clarify the terminology and the importance of the microflat in LaB6 cathodes. If you have any further questions, please don't hesitate to ask.

 

[charng]

Dear Lourie,

Thank you for your question regarding Lanthanum Hexaboride (LaB6) cathodes. The micron flat of a cathode refers to the top surface of the cathode, which is usually in the shape of a cone. This microflat is important because it is the point at which electrons are emitted from the cathode during the process of thermionic emission. The roundness and smoothness of this microflat is crucial for the efficiency and stability of the cathode.

In the case of the flat cathode, the term "complete flat" refers to the entire top surface of the cathode, which is usually a cylinder. However, in the case of the cone shaped cathode, the term "microflat" specifically refers to the top point of the cone.

I hope this clarifies your understanding of the terminology used in the documents you have attached. If you have any further questions, please do not hesitate to ask.

Best regards,