How many brass is 1 cubic meter?

The question is ambiguous because "brass" is not a unit of volume. Brass is an alloy of copper and zinc. You can't convert cubic meters (a volume) to brass (a material). You could, however, talk about the *mass* of brass in a cubic meter, but that would depend on the specific alloy of brass (the ratio of copper to zinc) since the density varies slightly depending on the composition.