Presentation is loading. Please wait.

Presentation is loading. Please wait.

How do defects and minor solute control the corrosion properties of solid solution alloys? Investigation of the effects of structural (order – disorder.

Similar presentations


Presentation on theme: "How do defects and minor solute control the corrosion properties of solid solution alloys? Investigation of the effects of structural (order – disorder."— Presentation transcript:

1 How do defects and minor solute control the corrosion properties of solid solution alloys? Investigation of the effects of structural (order – disorder transformation, relaxation), chemical (solute clusters, minor solute elements) and structural/chemical defects (solute rich and lean nanocrystals in an amorphous solid solution) were conducted at the nm-scale on corrosion using model engineered materials. Disordered and ordered crystalline Fe 50 Pd 50 show similar behavior in acidic Cl - solution, but the disordered structure has strong grain orientation dependent dissolution which is morphologically different than after ordering [1] The addition of minor solute elements alters the corrosion resistance of amorphous Al-Cu-Mg based alloys. Ni alloying lowers dissolution rate of Al. Ni also suppresses surface diffusion enabling the formation of a finer porous structure upon dealloying. Dealloying also leads to a rearrangement of Cu to the energetically favorable crystalline phase [2] CORROSION MECHANISMS IN AMORPHOUS SOLID SOLUTION ALLOYS: Role(s) of Minor Alloying Elements CORROSION MECHANISMS IN AMORPHOUS SOLID SOLUTION ALLOYS: Role(s) of Minor Alloying Elements John R. Scully, University of Virginia Main Campus, DMR 0906663 [1] Disordered Fe 50 Pd 50 Ordered Fe 50 Pd 50 Cu Al Cu Mg Al Cu Al Cu Mg Cu Al Mg Al Cu Mg Amorphous Alloy with beneficial minor solute Amorphous Alloy [2] Key results: Minor alloying element (Ni) plays an important role in the local corrosion behavior as well as dealloying of solid solutions. The solute rich amorphous alloys reorganizes into crystalline structure as dealloying proceeds. Electrochemistry Al Mg Cu Al Cu Mg Al Cu Al Cu Mg Al Cu Al Cu Ni Amorphous alloy with Ni Amorphous alloy no Ni Pure Al With NiNo Ni Nanoporous Cu formed in pits No NiWith Ni Crystallization by dealloying Disordered Fe 50 Pd 50 Key result: Structure and compositional ordering play a role in corrosion behavior EBSD Grain Orientation Index

2 Corrosion Education One high school (Martha Fox), 2 Undergraduates (H. Bindig, W. McCarthy), 3 graduate students (T. Aburada, N. Tailleart, D. Horton), and 1 post-doctoral researchers (H. Ha) contributed to NSF-supported project. Graduate & undergraduate, courses in corrosion taught in class and via distance learning (MSE 7080) and MSE 3080 for Made-in-Virginia for Engineers that brings engineering education to workers John R. Scully served on National Academy Study on Research Opportunities In Corrosion (ROCSE). Report due Fall 2010. Corrosion Education One high school (Martha Fox), 2 Undergraduates (H. Bindig, W. McCarthy), 3 graduate students (T. Aburada, N. Tailleart, D. Horton), and 1 post-doctoral researchers (H. Ha) contributed to NSF-supported project. Graduate & undergraduate, courses in corrosion taught in class and via distance learning (MSE 7080) and MSE 3080 for Made-in-Virginia for Engineers that brings engineering education to workers John R. Scully served on National Academy Study on Research Opportunities In Corrosion (ROCSE). Report due Fall 2010. (Title) II Name, Institution, DMR Award# Spatio-temporal Chaos in Systems of Broken Symmetry Eberhard Bodenschatz, Cornell University, DMR Award#0072077 Outreach NanoDays participation with nano-scale corrosion applications at local schools and museums cKITs (a set of corrosion experiments) supplied by National Association of Corrosion Engineers supplied to local K-12 schools Materials science and engineering demonstrations and lab tours are given to foster an interest in the physical sciences and materials science.Outreach NanoDays participation with nano-scale corrosion applications at local schools and museums cKITs (a set of corrosion experiments) supplied by National Association of Corrosion Engineers supplied to local K-12 schools Materials science and engineering demonstrations and lab tours are given to foster an interest in the physical sciences and materials science. CORROSION MECHANISMS IN AMORPHOUS ALLOYS: CRITICAL COMPOSITIONAL AND STRUCTURAL DEFECTS FOR LOCAL CORROSION CORROSION MECHANISMS IN AMORPHOUS ALLOYS: CRITICAL COMPOSITIONAL AND STRUCTURAL DEFECTS FOR LOCAL CORROSION J ohn R. Scully, University of Virginia Main Campus, DMR 0906663 Awards and Honors Nicole Tailleart, John R. Scully: Inaugural Award Recipients of the Corrosion Journal Best Paper Award, "User-selectable Barrier, Sacrificial Anode, and Active Corrosion Inhibiting Properties of Al-Co-Ce Alloys for Coating Applications." NACE International Conference, San Antonio, TX 2010. UVA's Center for Electrochemical Science and Engineering received the 2009 NACE Distinguished Organization Award John R. Scully: received the H.H. Uhlig Award, 2009 of the Electrochemical Society for excellence in corrosion research. Tomohiro Aburada was: One of twelve invited students internationally to present at Gordon Research Seminar, New London, NH 2010. Awards and Honors Nicole Tailleart, John R. Scully: Inaugural Award Recipients of the Corrosion Journal Best Paper Award, "User-selectable Barrier, Sacrificial Anode, and Active Corrosion Inhibiting Properties of Al-Co-Ce Alloys for Coating Applications." NACE International Conference, San Antonio, TX 2010. UVA's Center for Electrochemical Science and Engineering received the 2009 NACE Distinguished Organization Award John R. Scully: received the H.H. Uhlig Award, 2009 of the Electrochemical Society for excellence in corrosion research. Tomohiro Aburada was: One of twelve invited students internationally to present at Gordon Research Seminar, New London, NH 2010. Co-authors for Inaugural Best Paper in Corrosion Journal Award Recipients for NSF Funded Work on Amorphous Al-Co-Ce


Download ppt "How do defects and minor solute control the corrosion properties of solid solution alloys? Investigation of the effects of structural (order – disorder."

Similar presentations


Ads by Google