According to the Wikipedia page on Vibranium,
The Wakandan isotope possesses the ability to absorb all vibrations in the vicinity as well as kinetic energy directed at it.
This, along with the ineffectiveness of projectiles against Captain America's shield and Black Panther's suit indicate that vibranium is virtually impossible to deform. In addition, it appears to be highly resistant to heat, as Ultron's vibranium body only begins to melt under the combined fire of Iron Man, Thor, and the Vision. Yet in Marvel Comics and the MCU, Vibranium is seen molded into very complex forms, including Ultron's body and and Black Panther's suit.
How is Vibranium, a metal that is unaffected by kinetic impact of any kind, and highly resilient to heat, molded into the complex shapes used by characters in Marvel?