logging in or signing up Rome SHS Garrick Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 28 Category: Entertainment License: All Rights Reserved Like it (0) Dislike it (0) Added: October 31, 2007 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Microstructural Stability of Strong 9-12Cr Steels: Microstructural Stability of Strong 9-12Cr Steels www.msm.cam.ac.uk/phase-trans 650°CSlide2: Tempered martensite Tempered bainite Nam (1999)Slide3: Kimura et al., 2001Slide4: Thermodynamic stability 650°C Extrapolation of short-term data Fe-0.2C-1.5Mn wt% Stability: stored energySlide5: martensiteSlide6: martensiteSlide8: Long term stability requires precipitates which are close to equilibrium Laves, intermetallics, MX Metastable phases not appropriate Interfacial energy?Slide9: diffusion flux distance concentration c aq r c aq r 1 2 r 1 r 2 q a q CoarseningSlide11: Fraction 565 °CSlide12: Mole fraction 565 °CSlide13: Mole fraction Cr Cr concentration in ferrite 565 °CSlide14: c aq Concentration Distance c qa craq = caq + 2 caq s Va 1 - caq kT r cqa- caq Coarsening reduced if last term smallSlide15: Stability parameter caq (1 - caq ) cqa- caq Stability parameter = Comparison: Comparison 0.15C-0.25Si-0.50Mn-2.3Cr-1Mo- 0.10Ni 0.10C-0.60Si-0.40Mn-9.0Cr-1Mo-0.00Ni 1056 °C for 12 h, 740 °C for 13 hSlide17: 2 3 4 5 6 0 50 100 150 200 log(time/ h) 9Cr1Mo 2.25Cr1Mo Creep rupture stress/ MPaSlide18: Equilibrium precipitates Small interfacial energy (?) Small volume fraction Which precipitates are effective? Short term --> Long term data?Slide21: non-linear functionsSlide26: Brun, Robson, Narayan, MacKay & Bhadeshia, 1998Slide27: precipitates solid solution iron + microstructure 550 °C 600 °C Murugananth & Bhadeshia, 2001 105 h Creep Strength, 2.25Cr1Mo Slide28: Murugananth & Bhadeshia, 2001 elements in solutionSlide29: Kimura et al., 2001Slide31: Sourmail & Bhadeshia, 2004Slide32: Data from Abe, Masuyama, Sawaragi and Kimura, 2004Slide36: Difficult to achieve long-term stability using fine or metastable precipitates. Way forward is to avoid microstructure (Kimura, Abe) Extrapolation is optimal with neural networks You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Rome SHS Garrick Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 28 Category: Entertainment License: All Rights Reserved Like it (0) Dislike it (0) Added: October 31, 2007 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Microstructural Stability of Strong 9-12Cr Steels: Microstructural Stability of Strong 9-12Cr Steels www.msm.cam.ac.uk/phase-trans 650°CSlide2: Tempered martensite Tempered bainite Nam (1999)Slide3: Kimura et al., 2001Slide4: Thermodynamic stability 650°C Extrapolation of short-term data Fe-0.2C-1.5Mn wt% Stability: stored energySlide5: martensiteSlide6: martensiteSlide8: Long term stability requires precipitates which are close to equilibrium Laves, intermetallics, MX Metastable phases not appropriate Interfacial energy?Slide9: diffusion flux distance concentration c aq r c aq r 1 2 r 1 r 2 q a q CoarseningSlide11: Fraction 565 °CSlide12: Mole fraction 565 °CSlide13: Mole fraction Cr Cr concentration in ferrite 565 °CSlide14: c aq Concentration Distance c qa craq = caq + 2 caq s Va 1 - caq kT r cqa- caq Coarsening reduced if last term smallSlide15: Stability parameter caq (1 - caq ) cqa- caq Stability parameter = Comparison: Comparison 0.15C-0.25Si-0.50Mn-2.3Cr-1Mo- 0.10Ni 0.10C-0.60Si-0.40Mn-9.0Cr-1Mo-0.00Ni 1056 °C for 12 h, 740 °C for 13 hSlide17: 2 3 4 5 6 0 50 100 150 200 log(time/ h) 9Cr1Mo 2.25Cr1Mo Creep rupture stress/ MPaSlide18: Equilibrium precipitates Small interfacial energy (?) Small volume fraction Which precipitates are effective? Short term --> Long term data?Slide21: non-linear functionsSlide26: Brun, Robson, Narayan, MacKay & Bhadeshia, 1998Slide27: precipitates solid solution iron + microstructure 550 °C 600 °C Murugananth & Bhadeshia, 2001 105 h Creep Strength, 2.25Cr1Mo Slide28: Murugananth & Bhadeshia, 2001 elements in solutionSlide29: Kimura et al., 2001Slide31: Sourmail & Bhadeshia, 2004Slide32: Data from Abe, Masuyama, Sawaragi and Kimura, 2004Slide36: Difficult to achieve long-term stability using fine or metastable precipitates. Way forward is to avoid microstructure (Kimura, Abe) Extrapolation is optimal with neural networks