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Author Topic: if gamma rays has the highest energy.....can we use it for welding cuting  (Read 2532 times)

Offline taregg

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same question.....


Offline evan_au

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A coherent gamma ray source would be like a superpowerful laser.

However, each gamma rays photon contains so much energy that it usually takes a nuclear reaction, or an antimatter-matter annihilation to produce each photon. There are some bursts of gamma rays produced by energetic astronomical events (perhaps supernovae), and they have also been detected in Earth's atmosphere, perhaps from "Dark Lightning".

Gamma Rays are so powerful that they go through most materials (like X-Rays), so it is very hard to focus them in a tool, or to have them absorbed where you want them.

Offline CliffordK

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Other than the problem of being able to generate very powerful gamma rays, I think you're right that you would have a problem that most materials are transparent to gamma rays, or at least a large proportion of the gamma rays pass through fairly thick materials.

Perhaps you could cut lead with your gamma laser.

I think the idea with laser cutting is to choose a frequency that is 100% absorbed, and thus generates a lot of heat at the site of absorption.  There may be a slight benefit for cutting thick materials by using a frequency that is absorbed throughout the thickness of the material being cut, for example using x-rays on thick steel.  Refraction could be a problem and would require tight frequency control.

Steel, however, is often cut by oxidizing the very hot steel.

Offline alancalverd

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The production efficiency of x-rays is generally very low - less than 1% of the energy input to an x-ray tube comes out as useful radiation, and the technical problem of x-ray generation is to prevent the anode from melting. Adding a wiggler magnet to a synchrotron generates less heat per photon, but only if you ignore all the power that went into driving the synchrotron in the first place.

We have to look at gamma sources  to generate higher energy electromagnetic radiation by nuclear disintegration. Problem is, if you had a small source with sufficient gamma activity to melt, say, steel at a distance, wouldn't the source melt itself through self-absorption? 

You could start with a dispersed source and concentrate the radiation with a lens, but the refractive index of all materials for gamma radiation is tiny. Gravitational lensing? Fine, as long as you have a controllable supernova, a handy planet in the right place at the right time, and a few years to wait for the photons to reach you. And even then, the efficiency is infinitesimal.

I'm afraid the short answer is no.   

Offline JP

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Alan's correct.

If you want to do welding/cutting with photons, probably the best way is with a laser, and you can't make X-ray/gamma ray lasers because of the reasons Alan indicates (the optics just don't work very well at those wavelengths).  When you make a laser in the infra red range, which is fairly easy, you get a very high number of IR photons in a concentrated area, and these are generally easily absorbed as heat, which allows you to cut things.  CO2 lasers are in fact widely used for welding and cutting and can generate beam spot sizes on the order of 10 microns (the wavelength of the IR light it generates). 

Offline lightarrow

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Ok, but there is however a very difficult way to focalize at least X-rays: making them being reflected by metal surfaces at very high incident angles, near 90:

Maybe something similar, in theory, is possible even with soft gamma rays.

« Last Edit: 28/10/2013 16:13:38 by lightarrow »

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