In a rolling process, the state of stress of the material undergoing deformation is

A solid cylinder of diameter $$100$$ $$mm$$ and height $$50$$ $$mm$$ is forged between two frictionless flat dies to a height of $$25$$ $$mm.$$ The percentage change in diameter is

Hot die steel, used for large solid dies in drop forging, should necessarily have

Cold shut (lap) may occur in products obtained by: