You asked if metallurgy is deleted from the Class 10 chapter Metals and Non-metals.

Metallurgy is not fully deleted. The chapter is still there in the syllabus, but some parts of it have been removed from exams. The topics that are not included are basic metallurgical processes and corrosion with its prevention. These topics are still printed in the NCERT book, but you do not need to prepare them for exams.

So you still have to learn the main ideas of metals and non-metals like their properties, occurrence, and how they are extracted in a simple way. But you do not need to study the detailed steps of metallurgy or corrosion prevention.