What are these capsules made of?
This is the Expedition 47 return capsule that brought Astronauts Yuri Malenchenko, Timothy Peake, and Timothy Kopra back to Earth.
According to IFL Science!:
The display of the Soyuz TMA-19M was possible thanks to a partnership with the Russian space agency, Roscosmos, and the spacecraft’s manufacturer, RSC Energia.
There is more "char" in this photo, but copper-colored areas are still visible, lower right, and around flanges.
This photo in IFL Science! shows the char starting to peel off on the left and right edge. 2X crops are shown first, with the first one modified for "cooler" color temperature to color-balance the exposed structural metal, followed by the original image: