Depends on the specific pliers.
Good ones will typically be made out of a high carbon grade steel and heat forged to make it stronger than typical metals that one would want to cut.
Metal
Pliers are made of steel. There are plastic pliers for children too.
if i was to remove metal i would use pliers
Use Small .99 Pliers
Pliers with a special shape in the head (mine have 3 shapes) that compress a 'crimp' (a small metal tube) onto a wire.
Early plier-like devices were first used in ancient times to handle hot objects and coals in a cooking fire. When metalworking developed, pliers were used to handle the hot metal at the forge. The first pliers were made from wood, later from bronze.
Pliers are made of steel and as such will conduct heat -and electricity! However pliers whose handles are covered with rubber or plastic sleeves will be insulated against heat.
Steel with rubber insulated handles
They use small pliers to twist the metal around a small chunk of hair.
A metal bucket is made out of metal
Not all robots are made of metal but the majority of them are made of metal.
Usually I use metal, beads, pliers, wire cutters, beading wire, and crimp supplies.