PENGARUH POST WELD HEAT TREATMENT TERHADAP SIFAT FISIS, MEKANIS DAN KOROSI SAMBUNGAN LAS SPIRAL SAW PADA PIPA BAJA ASTM A252

• Main Authors: , IPICK SETIAWAN . ST, , M. Noer Ilman, S.T., M.Sc., Ph.D.
• Format: Theses and Dissertations NonPeerReviewed
• Published: [Yogyakarta] : Universitas Gadjah Mada 2011
• Subjects: ETD
• Online Access: https://repository.ugm.ac.id/89613/; http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=51641
• Institution: Universitas Gadjah Mada

Metal joint with welding system is increasingly used. i.e structure, piping or machine constuction. Some of the problems on welding is recidual stress dan over hardness which can lower weld toughness stress corrosion cracking. One effort to solve this problem is PWHT. PWHT has multiple functions, in addition to reducing residual stress, among others, PWHT increases ductility and improves toughness in weld metal and HAZ regions. Heating process with various temperature is expected to make optimum PWHT temperature. The experiment methods were carried out by depositing double V groove welds using submerged arc welding (SAW) with current of 375 A , voltage of 35 V and heat input of 2,8 kj/mm. Post weld heat treatment were carried out by holding the weld at various temperature of 450oC, 550oC and 650oC for 3 hour followed by furnace cooled. Subsequently, a sequence of test was carried out including microstructural examination, hardness measurement, tensile test and corrosion. Result show that increasing PWHT temperature lowers tensil strength but improves weld toughness. The optimum value is achieved at a temperature of 550o C with the toughness value of 81 J at 0O C temperarture.