Every year this dilemma strikes most of the students whether to opt for a good NIT but not the branch of choice or branch of choice at any NIT. What you should know is apart from the top five NITs, all the other NITs are equivalent. Therefore, go for the branch of your choice.
Now, answering that question that has been asked:
Looking at the placements, the Metallurgy department at NIT Jamshedpur has been better when compared to other NITs.
You can go for metallurgy at NIT Jamshedpur but, I will also suggest you give more preference to the branch of your choice.