🚀 go-pugleaf

Once upon a time, netspider4@lycos.com (Karl-Hugo Weesberg) said:
>   Date: 26 Oct 2004 00:59:51 -0700
>
>I want to send a rocket into outer space, but iron and copper seem to
>be too heavy.What material should I use for my rocket?

This is for writing a school paper, I would guess?

Traditionally, space rockets have used aluminum.  Aluminum is 
more lightweight per unit volume than steel, but not as strong.  
Using a sufficiently large thickness of aluminum for strength 
requirements results in higher overall stiffness (relative to 
modulus and cube of thickness), which is good for space 
applications.  Different alloys of aluminum have different 
strengths; some alloys reach strengths (UTS - ultimate tensile 
strength) of 70,000 psi.

Even though some modern plastics provide superior stiffness and 
strength per unit mass than aluminum, aluminum is still used in 
modern space programs because of its excellent heat conducting 
properties.  There are many systems on a space vehicle which 
generate heat, and in the absence of air there is no place for 
that heat to go except into the body of the vehicle itself.  If 
heat does not get transmitted away effectively, heat will build 
up and cause problems.  By making the outer hull of the vehicle 
aluminum, and giving all components a good thermal connection 
to the hull, a large radiating surface area is provided for 
heat dissipation.

You could try making a vehicle from high-strength, low-density 
plastics, and create a system of heat pumps throughout to take 
care of the heat problem (maybe terminating at a heat exchanger 
which vents gas to carry the heat energy away from the vehicle) 
but I suspect that might actually increase the overall mass of 
the vehicle.

To learn more about aluminum alloys and plastics, please consult 
the MaterialWeb database:
http://www.matweb.com/search/SearchSubcat.asp

Good luck,
-- TTK