Studi pengaruh perubahan tegangan pada larutan asam sulfat dan asam oksalat terhadap kekerasan dan ketebalan lapisan oksida hasil anodisasi aluminium tipe HD2G = Study of effect voltage changes of sulfuric acid and oxalic acid for hardness and thickness of oxide layer from anodizing process aluminium HD2G (Fakultas Teknik Universitas Indonesia, 2007)