Theoretically, I know that steam will start cooling slowly at constant volume to attain thermal equilibrium as per zeroth law of thermodynamics. After some time, steam will condense to water creating vacuum + water mixture because specific volume of steam is very high compared to water. This vacuum will result in catastrophic failure of metal ball. Question here is at what pressure metal will implode? Assume metal as steel and some thickness. You can take any values as per requirement to explain answer.
This vacuum will result in catastrophic failure of metal ball.
... that is not a true statement ... your questions also make an assumption that the sphere will implode $\endgroup$