metallurgy (the science)
Refers specifically to the scientific study of metals and their properties, as an academic or technical discipline.
He is majoring in metallurgy at university.
Compound of 冶金 (yakin, 'metallurgy') + 学 (gaku, 'study, science'). The term 冶金 is itself a Sino-Japanese word, from Chinese 冶金 (yějīn).