Lecture 17 - CHAPTER 17 CORROSION AND DEGRADATION ISSUES TO...

Info icon This preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 17 - 1 ISSUES TO ADDRESS... Why does corrosion occur ? What metals are most likely to corrode? How do temperature and environment affect corrosion rate? How do we suppress corrosion? CHAPTER 17: CORROSION AND DEGRADATION
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Chapter 17 - 2 Corrosion : -- the destructive electrochemical attack of a material. -- Al Capone's ship, Sapona, off the coast of Bimini. Cost: -- 4 to 5% of the Gross National Product (GNP)* -- this amounts to just over $400 billion/yr** * H.H. Uhlig and W.R. Revie, Corrosion and Corrosion Control: An Introduction to Corrosion Science and Engineering , 3rd ed., John Wiley and Sons, Inc., 1985. **Economic Report of the President (1998). Photos courtesy L.M. Maestas, Sandia National Labs. Used with permission. THE COST OF CORROSION
Image of page 2
Chapter 17 - 3 Two reactions are necessary: -- oxidation reaction: -- reduction reaction: Zn Zn 2 + + 2 e - 2H + + 2 e - H 2 (gas) Other reduction reactions: -- in an acid solution -- in a neutral or base solution O 2 + 4H + + 4 e - 2H 2 O O 2 + 2H 2 O + 4 e - 4(OH) - Adapted from Fig. 17.1, Callister 7e . (Fig. 17.1 is from M.G. Fontana, Corrosion Engineering , 3rd ed., McGraw-Hill Book Company, 1986.) CORROSION OF ZINC IN ACID Zinc Oxidation reaction Zn Zn 2+ 2e - Acid solution reduction reaction H + H + H 2 (gas) H + H + H + H + H + in the metal
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Chapter 17 - 4 STANDARD HYDROGEN (EMF) TEST Two outcomes: 0 o metal < V (relative to Pt)
Image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern