Karakteristik laju perambatan retak fatik Dan retak korosi tegangan Sambungan las baja tahan karat aisi 304 Dengan baja karbon rendah ss 400

Oleh :
Deni Tristanta - I0402007 - Fak. Teknik

The objective of this research is to investigate the characteristics of fatigue crack growth rate, stress corrosion cracking and fracture surface on weld joint of AISI 304 austenitic stainless steel with SS 400 low carbon steel. Welding process applied was Gas Metal Arc Welding (GMAW). The specimens were produced according to ASTM E 647-98 for fatigue crack growth rate (FCGR) test and ASTM G 30 & 123-98 for stress corrosion cracking (SCC) test. There is an initial crack on each FCGR test specimen, located on the weld metal and HAZ of each base metal. The observation to surface fracture from the result of the fatigue crack growth rate test is done by using SEM. The result shows that the FCGR on HAZ of stainless steel (C = 2x10-12 and m = 3,78) is lower than those on HAZ of carbon steel (C = 8x10-17 and m = 7,89). As the weld metal has higher properties, the FCGR on this area can not be investigated. The fracture surface of FCGR test specimens indicates the transgranular and intergranular fracture modes. During 380 hours of SCC testing, crack was not found. During 329 hours of SCC testing, pitting corrosion was found on HAZ of stainless steel.