Difference between modern age and the age of metals?

Answer 1

I assume by "age of metals" you mean the "iron age", "bronze age" etc, respectively.

In this naming system, the age's material indicates the highest technological capacity in that society. In the bronze age, bronze was the most useful material that could be worked. In the iron age, iron was prevalent. Today, we are adept at working nearly every material we know of, and regularly develop new ones, so the modern age seems to have stepped beyond specific metal dependency.

In material science, there is also the tendency to move away from metal-alloy materials toward plastics, ceramics, and composite materials other than alloys. In this context, the "age of metals" may refer to all the way from the development of bronze around the end of the Neolithic era (end of the Stone Age, in layman's terms) to present day, and beyond, since metal use has formed the core of most societies throughout this time period (a notable exception being the majority of societies from the Americas). Some material scientists and engineers believe we are nearing the end of relying on metals as a material, though current consumptive behavior indicates that there is still a long way to go. There are potential materials available - spider silk and carbon nanotubes being the most well known, but development of an economically viable method of producing either of these materials is still in its infancy. An additional problem in that regard is the different material forming methods necessary with such a significant change from metals - all metals perform fairly similarly in the standard forming processes - many nonmetal materials behave in vastly different manners.