Creep properties of service-ezposed Alloy 625 after resolution annealing treatment and microstructural assessment using ultrasonic waves
Creep rupture properties of alloy 625,that has been in service for 60,000 hours at 993 K,have been evaluated after subjecting the service-exposed material to re-solution annealing treatment at 1433K for one hour.Creep tests were carried out at various temperatures between 923 and 1173K,and the rupture times varied up to 32,000 hours.Isostress and Larson-Miller parametric methods were employed to estimate the residual creep rupture life.Creep rupture strength and rupture ductility recovered substantially following re-solution annealing treatment.The variations in rupture life and rupture ductility with creep test variables have been rationalised on the basis of the complex microstructural changes that occurred in the material during creep.An attempt was also made to asses microstructural changes in this alloy using ultrasonic waves and correlation with tensile properties.Alloy 625 was aged at various temperatures in the range 923 to 1123K to produce different microstructures.Ultrasonic velocity was measured to characterise the microstructures.Tensile properties and hardness were determined using ball indentation technique.A direct correlation has been observed between ultrasonic velocity and mechanical properties.
Alloy 625 Creep life eztension Thermal ageing Microstructure Rupture ductility Ultrasonic testing
S.L.Mannan M.D.Mathew
National Engineering College,Kovilpalti.Tamil Nadu 628 503,India Mechanical Metallurgy Division,IGCAR,Kalpakkam,Tamil Nadu 603 102,India
国际会议
成都
英文
23-30
2009-10-16（万方平台首次上网日期，不代表论文的发表时间）