Pengaruh Masukan Panas Terhadap Penetrasi, Kekerasan, dan Struktur Mikro pada Pengelasan Autogenous Tungsten Inert Gas (TIG) Aluminium Paduan AA1100 = Effect of Heat Input on Penetration, Hardness, and Microstructure in Autogenous Tungsten Inert Gas (TIG) Welding of Aluminum Alloy AA1100