1. CORROSION… The Best Kept Secret in the Western World
Terry May President, NACE Foundation
Introduction
Not a professional educator
Engineer and training instructor
New addition to curriculum
Important but unknown topic
Corrosion, rust, oxidation, deterioration, cancer?
Why is this important?

2. Corrosion & Society
Discuss the 3 Primary effects of corrosion and how it affects our society

3. Corrosion & Society
Discuss the 3 Primary effects of corrosion and how it affects our society

4. Corrosion & Society
Discuss the 3 Primary effects of corrosion and how it affects our society

5. Cost of Corrosion in 1998 GNP
Give Background on Cost of Corrosion Study and Primary Results

6. Money
To put in perspective – the annual cost of all the natural disasters in the USA. (Hurricanes, tornadoes, tropical storms, floods, fires etc)
$17 Billion
Corrosion Costs the US economy $276 Billion per Year or 16 times as much as all the natural disasters combined
More than $1000/year/person

7. 25+% could be saved using existing technologies
Money
25+% could be saved using existing technologies

8. Environment
500,000+ miles of pipelines in the US

9. Environment

10. Safety
Bellingham, WA
1999 Pipeline explosion killed 3 people

11. Safety
Carlsbad, NM

12. Safety
Air Aloha

13. Safety Lowes Motor Speedway
15% of almost 600,000 bridges in the USA are structurally deficient because of corrosion

14. Application to Various Industries
Pipelines
Underground Storage Tanks
Industrial Plants
Power Generation
Transportation
Marine
Waterworks
Petrochemical Plants
Pulp and Paper
Real Estate
Private Homes

20. What is Corrosion?
Corrosion is an electrochemical reaction between a metal and its environment
Corrosion is the tendency of a metal to return to its original state
Corrosion involves the flow of DC current
Corrosion is a natural process

21. What causes Corrosion? Dissimilar metal Differential Aeration
Environment concentration differences
Bacteria
Stress
Erosion
Temperature effects

22. What does Corrosion look like?
Uniform
Pitting
Stress Cracking
Intergranular
Crevice Attack
Erosion-Corrosion

23. General
Corrosion

24. Pitting

25. Crevice Corrosion

26. Galvanic Corrosion

27. Practical Galvanic Series
Magnesium Volts
Zinc
Aluminum
Steel (clean or shiny) to -0.8
Steel (rusty) to -0.5
Cast Iron
Lead
Copper or brass
Mill scale on steel
Carbon or graphite
ACTIVE
Standard electromotive series based on standard hydrogen reference.
Galvanic series may vary slightly and are specific to an environment
PASSIVE

28. Flashlight Battery An engineered corrosion reaction
Zinc/Carbon cell connected with a conductive electrolyte
Life depends on current load

29. Graphite-Zinc Battery
Protective casing
Pitch Seal
Electrolyte paste
(ammonium chloride
and zinc chloride)
Air Space
Zinc
Separator
Carbon rod
Negative terminal

30. What conditions are required for corrosion to occur?
An anode and a cathode – locations with a difference in electrical potential (voltage) between them
A metallic connection between the two points
Both locations exposed to the same environment

31. Four Conditions of a Corrosion Cell
Anode - where oxidation occurs
Cathode - where reduction occurs
Electrolyte - where ion migration occurs
Metallic path - where electrons migrate from the anode to the cathode

32. Single Corrosion Cell e- e- e- e- e- e- e- e- e- e- e- CATHODIC SITE
Microscopic View
CATHODIC
SITE
ANODIC SITE e- e- e- e- e- e- e- e- e- e- e- H
Fe++
Fe++ H H+ H+
Fe++ H
Fe++
OH- H+
Fe++
OH- H+ H+
Fe++
OH- H+
Fe(OH)2
Fe(OH)2 H+
Fe(OH)2

33. The Corrosion Cell
Metallic corrosion is an “electrochemical reaction” which involves :
a transfer of electrons
oxidation - loss of electrons (corrosion)
reduction - gain of electrons (protection)
migration of ions

34. Corrosion Cell Electrolyte Metallic Path e e Cathode Anode e e H+ H+Cu Fe e e H+ H+
Fe++
H+OH—
Electrolyte
H+OH—

35. Structure (metallic path)
Practical Case Showing Conventional Current Flow E
Corrosion Current
Electrolyte (soil)
Cathode
Anode
Structure (metallic path)

36. Electrochemical Reactions
Anode: (Oxidation)
Fe  Fe++ + 2e—
Cathode : (reduction)
2H+ + 2e—  H2
3O2 + 6H2O + 12e– 12OH—
O2 + 4H+ + 4e—  2H2O
Electrolyte
H2O  H+ + OH—

37. Oxidation Reaction Anodic Process ANODE ELECTROLYTE e e e e e e e e e- e - e - ++ Fe e - e - e - e - Fe ++ e - Fe ++ e - Fe ++ Fe ++ e -
ANODE e - e - Fe ++ e - Fe ++ e - e - e - e - Fe ++ e - Fe ++
Anodic Process

38. Reduction Reaction CATHODE Cathodic Process ELECTROLYTE e e e e e e e- H + e - H + H H H H e - e - e - H + e - H
CATHODE e - H + H + e - + e - H + e - H H + e - e - H + e - e - H + H + e - H + e - e - H + H
Cathodic Process

39. Current Flow in a Basic Galvanic Cell

40. Methods of Corrosion Control
Coating
Cathodic Protection
Environment Control
Material Selection
Design

41. Microscopic View of a Corrosion Cell
Anode
Cathode
Microscopic Corrosion Cell on the Surface of a Pipeline

42. Cathodic Protection on a Structure (Macroscopic view)
Anode
Cathode
Metallic Connection
Electrolyte
Cathodic Protection Anode
Cathodic Protection
Current Applied

43. Typical Application of Cathodic Protection
Underground pipelines
Underground storage tanks
Bottoms of on grade storage tanks
Interiors of water storage tanks
Condenser and heat exchanger water boxes
Reinforced concrete
Doesn’t work in the atmosphere (Automobiles)
Underground pipelines
Underground storage tanks
Bottoms of on grade storage tanks
Interiors of water storage tanks
Condenser and heat exchanger water boxes
Reinforced concrete
Doesn’t work in the atmosphere (Automobiles)

44. Preserving the Past

45. Preserving the Past
Give examples of corrosion control technologies for protection of Titanic artifacts

46. Preserving the Past
Give examples of corrosion control technologies for protection of Titanic artifacts

47. Statue of Liberty
Discuss preservation of Statue of Liberty

48. Just Flying along, enjoying the ride....
what's so cool is they actually pay  me to do this! 

49. Hmmm. Strange sound. Something feels different.

50. Hey, why am I looking up.??

51. Whoa here, what the hell? Controls aren't working

52. Time for a mirror check. Hey, where's the rest of my F-15.?

53. Uh oh, it's over there. I think I've got a definite "Aw, sh
Uh oh, it's  over there.  I think I've got a definite "Aw, sh*t" going here...

54. I gotta wonder, am I the first guy to ever  experience " cockpit-airframe separation anxiety".

55. I'm outta here. But first the canopy has to go.

56. Hey GREAT! That worked as advertised. Things are looking up!

57. OK, now it's my turn to go.  I'm gone - soon as I  find the eject handle.

58. Oh yeah, that's what I'm talking about
Oh yeah, that's what I'm talking about.   Looks like it's going to be just another "average day at the office."