Abstrak
Friction stir welding (FSW)adalahpenyambungan material dalamkeadaanpadatdantidakmenggunakanbahantambahan. FSW awalnyadiaplikasikanuntukpenyambungan material logam, dansekarangdiaplikasikanuntuk material non logamsepertipolimer.Polypropylene (PP) merupakanpolimer yang banyakdigunakandalamduniaindustri. PP memilikikonduktivitaspanasrendah, sehinggaperluditambahkanpemanastambahanuntukmembantu proses pengelasannya.
Material yang digunakanadalah 2 buah plat PP dengandimensi 200x40x6 mm. Parameter pengelasan yang digunakanyaiturotational speed 1140 rpm,sudut kemiringan tool 20danshoulder depth of plunge0,2 mm. Variasitransverse speed 7,3; 13; 24,5; dan 33,5 mm/min denganpemanasdantanpapemanas.Hasillasdiujitarikdan bending denganmenggunakanmesin UTM dandiujifotomakrountukmenganalisapatahan.
Hasillasdenganpemanastambahanmemilikinilaikekuatanmekanik yang lebihtinggidaripadatanpapemanas.Kekuatanmekaniksemakinmeningkatseiringdenganpenurunantransverse speed.Kekuatanmekaniktertinggidiperolehpadavariasitransverse speed 7,3 mm/min denganpemanastambahan, yaitu 10,73 MPauntukujitarik; 39,33 MPauntukujiface bending; dan21,99 MPauntukujiroot bending.
Kata kunci :friction stir welding, polypropylene,transverse speed,danpemanastambahan,
Abstract
Friction stir welding (FSW) is a solid-state joining process without use additional material. FSW initially applied to joint two piece of metal, and then began to be applied to non-metallic materials such as polymers. Polypropylene (PP) is one kind of thermoplastic polymer used in a wide variety industry. PP has low thermal conductivity, so additional heaterapplied to help welding process.
Two pieces of polypropylene with dimention 200x40x6 mm was usedas based material. Welding parameters in process used are 1140 of rotational speed, 2o of tilt angel, and 0,2 mm shoulder depth of plunge. Variation transverse speed of FSW process are 7,3; 13; 24,5; and 33,5 mm/min with and without additional heater. UTM was used for tensile and bending testing, and Stereozoom was used for macrostructure fracture investigation.
The result showed that welds with additional heater have the higher mechanical strength than without additional heater. Mechanical strength increase along with decreasing of transverse speed. It led specimen with variation of transverse speed 7,3 mm/min with additional heater has the highest mechanical strength,10,73 Mpa for tensile; 39,33 Mpa for face bending and 21,99 Mpa for root bending.
Keywords :friction stir welding, polypropylene, transverse speed, and additional heating.