Yes, you can do a Diploma in Metallurgy directly after 12th standard in India.These programs are designed for students who have completed their 12th grade (Class XII) and want to gain vocational or technical skills in a specific field. Metallurgy is a common specialization offered in many diploma programs.  Numerous private institutes also offer Diploma in Metallurgy programs. Ensure these institutes are affiliated with a recognized university or accreditation body.

https://engineering.careers360.com/articles/how-prepare-for-gate-metallurgy-engineering

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Yes, you can definitely pursue a diploma in Metallurgy without doing a BE (Bachelor of Engineering) or BTech (Bachelor of Technology) directly after 12th standard in India.
The basic eligibility for a diploma in Metallurgy is passing your 12th standard with Physics and Chemistry, and sometimes Mathematics as mandatory subjects. The percentage requirement for admission can vary depending on the specific institution.

https://school.careers360.com/download/ebooks/diploma-courses-after-12th-science

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