Hi,
It is not a question of material science (which might be subject to improvement). It is a question of elements and interactions. Radiation loses energy either by ionizing the materials it goes through or scattering off of the material (principally the nuclei) it goes through. The effectiveness of either process depends on the type and energy of the radiation and the element it is interacting with.
Now, for any specific type and energy of radiation, there is an element that would make the best shield. But even that element has to be thick enough that either the ionization per unit length slows or stops the radiation, or the areal density of the projected scatterers will give a sufficiently high probability of stopping or reflecting the radiation.
Any shield made of a composite will not be as good as one made only of the best material in that composite. However, some materials cannot be used in pure form, and others are much easier to handle in a composite.
The situation is not a question of better engineering, it is one of basic physics.
--Pete
(01-25-2011, 09:33 PM)kandrathe Wrote: I'm asking and wondering if we've advanced the field of materials sciences ( e.g. dense composites and compounds, absorption, or deflection), or it we still tend to think about shielding as calculating it as the number of cm of "dense" and "cheap" elemental materials needed.
It is not a question of material science (which might be subject to improvement). It is a question of elements and interactions. Radiation loses energy either by ionizing the materials it goes through or scattering off of the material (principally the nuclei) it goes through. The effectiveness of either process depends on the type and energy of the radiation and the element it is interacting with.
Now, for any specific type and energy of radiation, there is an element that would make the best shield. But even that element has to be thick enough that either the ionization per unit length slows or stops the radiation, or the areal density of the projected scatterers will give a sufficiently high probability of stopping or reflecting the radiation.
Any shield made of a composite will not be as good as one made only of the best material in that composite. However, some materials cannot be used in pure form, and others are much easier to handle in a composite.
The situation is not a question of better engineering, it is one of basic physics.
--Pete
How big was the aquarium in Noah's ark?