As per your score, chances are less to get IITs and top NITs but if you want you can try for lower NITs.

And if you are interested in M.Tech in Metallurgy then you can read below given points -
Metallurgy Engineering has good scope in India as
India is rich in mineral deposits like metal extraction is an important industrial activity. So you can get a chance to get placed in metal extraction units, heavy machine manufacturing enterprises, electrical companies, and construction companies.
Metallurgy being a basic engineering science has universal application across all manufacturing sectors.
Metal extractors like Tata Steel, Steel Authority of India (SAIL), Hindustan Copper Limited, Hindalco Industries Limited, and Jindal Steel are the major recruiters of Metallury Engineers.

Hope this helps!!!

So decide wisely.

Good Luck!!!