6. Uu, nhuoc diem cua thep dai Thep dai hay con goi la day dai thep, day dai khong gi, day dai thep khong gi. Day dai thep san xuat bang phuong phap can nguoi duoc xu ly son dau hoac son tinh dien cao cap, chia thanh 3 loai chinh: day dai thep dau, day dai thep son tinh dien, day dai thep ma kem.