ANALISIS MULTIPLE REPAIR PADA MATERIAL PIPA STAINLESS STEEL 06Cr19Ni10 DENGAN PROSES LAS GTAW TERHADAP KUAT TARIK, KEKERASAN, DAN STRUKTUR MIKRO
In the process of welding stainless steel pipes do not escape with a defect results so that the repair process must be done immediately to eliminate a discontinuity or defect in the weld metal. The repair process once there may still be more defects while multiple repairs will cause additional thermal cycles, which greatly affect significant microstructure changes, deformation and mechanical properties of the material. This research aimed to determine the analysis of multiple repair on stainless steel pipe material. Using a 2" pipe test coupon with a single V connection design and the repair process is carried out half of the thickness of the material. The results of the tensile strength value test shown a downward trend due to the increasing number of repairs. Hardness test results produce the highest average value in the fusion line area, especially the part affected by the repair process namely the top specimen area due to the smaller grain size and the ferrite phase formed is increasing. The results of micro testing showed that the visible morphology was white austenite grains and black ferrite grains. However, with the increase in the number of ferrite phase repairs, the percentage increases. From the results all tests met the acceptability permitted by the procedures and standards used.