Seminar Reminder for Tom Kanaby's Ph.D. Final, Tuesday, July 18, at 8:00 a.m., in ARMS 1103, "Cyclic Nano-Indentation Investigation of Plasticity in Case Hardened Bearing Steels"
Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Cyclic Nano-Indentation Investigation of Plasticity in Case Hardened Bearing Steels" By Thomas R. Kanaby Purdue MSE Ph.D. Final Exam Advisor: Professor David F. Bahr ABSTRACT Longevity of high performance gears and bearings is often limited by the spall crack initiation from rolling contact fatigue during service. Demands for performance and reliability are shifting some designs from through hardened bearing alloys to case hardened alloys. This shift presents a challenge for understanding ratcheting mechanisms that lead to crack initiation and mechanical predictions of bearing endurance. Advancement of case hardening alloys and process development are hampered by expensive and problematical contact fatigue tests, residual stress and other contributions to endurance, and assumptions used in predictions about properties in the plastically graded case. This effort asserts that the fine differences in structure result in differences in strain accumulation mechanisms that are discernible through micron level plasticity testing. A direct evaluation of microplasticity of case hardened bearing steels through cyclic nano-mechanical indention tests was employed to develop an understanding of the changes in strain energy accumulation during cycling. Cyclic indentation at various depths within graded microstructures from case hardened samples was performed within the typical active plastic zone in bearing alloys. With this technique, differences in microplasticity between samples of similar composition and hardness were discerned, and trends in matrix elastic losses with fatigue cycling were isolated from residual stress and other variables that cloud fatigue performance analysis. This method can be utilized in development and optimization of alloys and processing for high cycle and contact fatigue applications. Date: Tuesday, July 18, 2017 Time: 8:00 A.M. Place: ARMS 1103
Reminder for Tom Kanaby's Ph.D. Final Seminar tomorrow, Thursday, August 18, in ARMS 1103, at 8:00 a.m. From: Son, Rosemary E Sent: Tuesday, July 11, 2017 2:04 PM To: 'msefaculty-list@ecn.purdue.edu' <msefaculty-list@ecn.purdue.edu>; 'msegradstudent-list@ecn.purdue.edu' <msegradstudent-list@ecn.purdue.edu>; 'msepostdoc-list@ecn.purdue.edu' <msepostdoc-list@ecn.purdue.edu> Cc: 'Tom Kanaby' <kanabyt@yahoo.com>; Cline, Vicki L. <vicline@purdue.edu>; Tomar, Vikas <tomar@purdue.edu>; Son, Rosemary E <son39@purdue.edu> Subject: Seminar Reminder for Tom Kanaby's Ph.D. Final, Tuesday, July 18, at 8:00 a.m., in ARMS 1103, "Cyclic Nano-Indentation Investigation of Plasticity in Case Hardened Bearing Steels" Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Cyclic Nano-Indentation Investigation of Plasticity in Case Hardened Bearing Steels" By Thomas R. Kanaby Purdue MSE Ph.D. Final Exam Advisor: Professor David F. Bahr ABSTRACT Longevity of high performance gears and bearings is often limited by the spall crack initiation from rolling contact fatigue during service. Demands for performance and reliability are shifting some designs from through hardened bearing alloys to case hardened alloys. This shift presents a challenge for understanding ratcheting mechanisms that lead to crack initiation and mechanical predictions of bearing endurance. Advancement of case hardening alloys and process development are hampered by expensive and problematical contact fatigue tests, residual stress and other contributions to endurance, and assumptions used in predictions about properties in the plastically graded case. This effort asserts that the fine differences in structure result in differences in strain accumulation mechanisms that are discernible through micron level plasticity testing. A direct evaluation of microplasticity of case hardened bearing steels through cyclic nano-mechanical indention tests was employed to develop an understanding of the changes in strain energy accumulation during cycling. Cyclic indentation at various depths within graded microstructures from case hardened samples was performed within the typical active plastic zone in bearing alloys. With this technique, differences in microplasticity between samples of similar composition and hardness were discerned, and trends in matrix elastic losses with fatigue cycling were isolated from residual stress and other variables that cloud fatigue performance analysis. This method can be utilized in development and optimization of alloys and processing for high cycle and contact fatigue applications. Date: Tuesday, July 18, 2017 Time: 8:00 A.M. Place: ARMS 1103
Tom Kanaby's Ph.D. Final Seminar is tomorrow, Tuesday, July 18, at 8:00 a.m., in ARMS 1103. Sorry for the confusion. From: Son, Rosemary E Sent: Monday, July 17, 2017 1:47 PM To: 'msefaculty-list@ecn.purdue.edu' <msefaculty-list@ecn.purdue.edu>; 'msegradstudent-list@ecn.purdue.edu' <msegradstudent-list@ecn.purdue.edu>; 'msepostdoc-list@ecn.purdue.edu' <msepostdoc-list@ecn.purdue.edu> Cc: 'Tom Kanaby' <kanabyt@yahoo.com>; Cline, Vicki L. <vicline@purdue.edu>; Son, Rosemary E <son39@purdue.edu> Subject: FW: Seminar Reminder for Tom Kanaby's Ph.D. Final, Tuesday, July 18, at 8:00 a.m., in ARMS 1103, "Cyclic Nano-Indentation Investigation of Plasticity in Case Hardened Bearing Steels" Reminder for Tom Kanaby's Ph.D. Final Seminar tomorrow, Thursday, August 18, in ARMS 1103, at 8:00 a.m. From: Son, Rosemary E Sent: Tuesday, July 11, 2017 2:04 PM To: 'msefaculty-list@ecn.purdue.edu' <msefaculty-list@ecn.purdue.edu<mailto:msefaculty-list@ecn.purdue.edu>>; 'msegradstudent-list@ecn.purdue.edu' <msegradstudent-list@ecn.purdue.edu<mailto:msegradstudent-list@ecn.purdue.edu>>; 'msepostdoc-list@ecn.purdue.edu' <msepostdoc-list@ecn.purdue.edu<mailto:msepostdoc-list@ecn.purdue.edu>> Cc: 'Tom Kanaby' <kanabyt@yahoo.com<mailto:kanabyt@yahoo.com>>; Cline, Vicki L. <vicline@purdue.edu<mailto:vicline@purdue.edu>>; Tomar, Vikas <tomar@purdue.edu<mailto:tomar@purdue.edu>>; Son, Rosemary E <son39@purdue.edu<mailto:son39@purdue.edu>> Subject: Seminar Reminder for Tom Kanaby's Ph.D. Final, Tuesday, July 18, at 8:00 a.m., in ARMS 1103, "Cyclic Nano-Indentation Investigation of Plasticity in Case Hardened Bearing Steels" Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Cyclic Nano-Indentation Investigation of Plasticity in Case Hardened Bearing Steels" By Thomas R. Kanaby Purdue MSE Ph.D. Final Exam Advisor: Professor David F. Bahr ABSTRACT Longevity of high performance gears and bearings is often limited by the spall crack initiation from rolling contact fatigue during service. Demands for performance and reliability are shifting some designs from through hardened bearing alloys to case hardened alloys. This shift presents a challenge for understanding ratcheting mechanisms that lead to crack initiation and mechanical predictions of bearing endurance. Advancement of case hardening alloys and process development are hampered by expensive and problematical contact fatigue tests, residual stress and other contributions to endurance, and assumptions used in predictions about properties in the plastically graded case. This effort asserts that the fine differences in structure result in differences in strain accumulation mechanisms that are discernible through micron level plasticity testing. A direct evaluation of microplasticity of case hardened bearing steels through cyclic nano-mechanical indention tests was employed to develop an understanding of the changes in strain energy accumulation during cycling. Cyclic indentation at various depths within graded microstructures from case hardened samples was performed within the typical active plastic zone in bearing alloys. With this technique, differences in microplasticity between samples of similar composition and hardness were discerned, and trends in matrix elastic losses with fatigue cycling were isolated from residual stress and other variables that cloud fatigue performance analysis. This method can be utilized in development and optimization of alloys and processing for high cycle and contact fatigue applications. Date: Tuesday, July 18, 2017 Time: 8:00 A.M. Place: ARMS 1103
participants (1)
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Son, Rosemary E