Aluminum converted into copper
 

how we can calculation of SWG #19 aluminum wire into copper wire?
how we can calculation copper strip into round wire in swg.?

With a calculator. You'll have to use the cross sectional area of the cable to figure it out for the strip. For the aluminum to copper you'll have to wait for a European electrician. I believe that the equivalent of our 18 gauge but I'm not certain. If you use 19swg copper you know your covered though

The NEC has all the values you are looking for. However, the NEC is an American standard and refers to AWG wire sizes. But you could find the circular mills to get a very close or exact ohm value. Meaning if you can convert your number 19 wire to what we use in the US, the code book has this information.

Use the formula associated with the figure in this link.
http://en.wikipedia.org/wiki/Electri...d_conductivity

You only need the cross sectional area of the round wire and of the strip since both conductors are copper of arbitrary length.

IIRC, aluminum has 1.6x the resistivity of copper. Iron has about 6x.