section 08 (nxpowerlite).ppt
TRANSCRIPT
![Page 1: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/1.jpg)
Haward Technology Middle East 1Section 8
AWS Certified Welding Inspector (CWI)
Section 8
Welding Metallurgy for the Welding Inspector
![Page 2: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/2.jpg)
Haward Technology Middle East 2Section 8
AWS Certified Welding Inspector (CWI)
Metallurgy
“The science dealing with the internal structure of metals and metal
properties ”
![Page 3: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/3.jpg)
Haward Technology Middle East 3Section 8
AWS Certified Welding Inspector (CWI)
Welding Metallurgy
“Concerned with the changes occurring in metals during welding”
![Page 4: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/4.jpg)
Haward Technology Middle East 4Section 8
AWS Certified Welding Inspector (CWI)
Discussion Topics
Structures
Changes on heating
Changes on cooling
Heat treatments
Alloying
Phases
![Page 5: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/5.jpg)
Haward Technology Middle East 5Section 8
AWS Certified Welding Inspector (CWI)
Atomic Structure
Matter made up of atoms
Atoms are very small
Electrons orbit atomic nuclei
Have a home location in solids
Oscillate around home position
![Page 6: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/6.jpg)
Haward Technology Middle East 6Section 8
AWS Certified Welding Inspector (CWI)
Atomic Structure - Simple Cubic
![Page 7: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/7.jpg)
Haward Technology Middle East 7Section 8
AWS Certified Welding Inspector (CWI)
Home Location
![Page 8: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/8.jpg)
Haward Technology Middle East 8Section 8
AWS Certified Welding Inspector (CWI)
Solids
Minimum internal energy
Atoms fixed in place
Atoms have ‘home’ position
Atoms vibrating
Orbiting electrons
Crystalline structure
![Page 9: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/9.jpg)
Haward Technology Middle East 9Section 8
AWS Certified Welding Inspector (CWI)
Liquids
Higher internal energy
Atoms free to move
Atoms vibrating more
Orbiting electrons
No fixed structure
![Page 10: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/10.jpg)
Haward Technology Middle East 10Section 8
AWS Certified Welding Inspector (CWI)
Solid vs Liquid
![Page 11: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/11.jpg)
Haward Technology Middle East 11Section 8
AWS Certified Welding Inspector (CWI)
Thermal expansion on Heating
Thermal contraction on Cooling
![Page 12: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/12.jpg)
Haward Technology Middle East 12Section 8
AWS Certified Welding Inspector (CWI)
Welding Stresses (Tensile)
Remain after welding is completed (residual stress)
Can cause distortion
• (welding stress exceeds yield strength of material)
Can cause cracking
• (welding stress exceeds tensile strength of material)
Residual stress can be as high as yield strength
Relieved by three methods
![Page 13: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/13.jpg)
Haward Technology Middle East 13Section 8
AWS Certified Welding Inspector (CWI)
Stress Relieving
Thermally
Vibratory
Peening
![Page 14: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/14.jpg)
Haward Technology Middle East 14Section 8
AWS Certified Welding Inspector (CWI)
Crystal Structures
BCC - Body Centered Cubic
FCC - Face Centered Cubic
HCP - Hexagonal Close Packed
BCT - Body Centered Tetragonal
![Page 15: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/15.jpg)
Haward Technology Middle East 15Section 8
AWS Certified Welding Inspector (CWI)
Common Crystal Structures
![Page 16: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/16.jpg)
Haward Technology Middle East 16Section 8
AWS Certified Welding Inspector (CWI)
Metal Solidification
![Page 17: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/17.jpg)
Haward Technology Middle East 17Section 8
AWS Certified Welding Inspector (CWI)
Grain Size Effects
Fine grained materials• Have good tensile strength• Have good ductility• Have good low temperature properties
Coarse grained materials• Have slightly lower strength• Are slightly less ductile• Have good high temperature properties
![Page 18: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/18.jpg)
Haward Technology Middle East 18Section 8
AWS Certified Welding Inspector (CWI)
Alloying
“Adding elements to change mechanical or physical properties”
![Page 19: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/19.jpg)
Haward Technology Middle East 19Section 8
AWS Certified Welding Inspector (CWI)
Interstitial Alloying
![Page 20: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/20.jpg)
Haward Technology Middle East 20Section 8
AWS Certified Welding Inspector (CWI)
Interstitial Alloying -Results in Lattice Distortion
![Page 21: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/21.jpg)
Haward Technology Middle East 21Section 8
AWS Certified Welding Inspector (CWI)
Substitutional Alloying
![Page 22: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/22.jpg)
Haward Technology Middle East 22Section 8
AWS Certified Welding Inspector (CWI)
Substitutional Alloying -Results in Lattice Distortion
![Page 23: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/23.jpg)
Haward Technology Middle East 23Section 8
AWS Certified Welding Inspector (CWI)
Microstructures
Metals composed of grains (crystals)
Very small
Separated by grain boundaries
Different phases within grains
![Page 24: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/24.jpg)
Haward Technology Middle East 24Section 8
AWS Certified Welding Inspector (CWI)
Microstructure of Iron
![Page 25: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/25.jpg)
Haward Technology Middle East 25Section 8
AWS Certified Welding Inspector (CWI)
Iron-Carbon Phase Diagram
![Page 26: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/26.jpg)
Haward Technology Middle East 26Section 8
AWS Certified Welding Inspector (CWI)
Phases in Steel
Ferrite
Cementite
Austenite
Bainite
Pearlite
Martensite
![Page 27: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/27.jpg)
Haward Technology Middle East 27Section 8
AWS Certified Welding Inspector (CWI)
Cooling Rates
Slow - Pearlite - Softest
Moderate - Bainite
Fast - Martensite - Hardest
![Page 28: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/28.jpg)
Haward Technology Middle East 28Section 8
AWS Certified Welding Inspector (CWI)
Lamellar Appearance of Pearlite
![Page 29: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/29.jpg)
Haward Technology Middle East 29Section 8
AWS Certified Welding Inspector (CWI)
Martensite
![Page 30: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/30.jpg)
Haward Technology Middle East 30Section 8
AWS Certified Welding Inspector (CWI)
Tempering
“Restores ductility and toughness and reduces strength and hardness”
![Page 31: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/31.jpg)
Haward Technology Middle East 31Section 8
AWS Certified Welding Inspector (CWI)Effects of
Tempering Temperatures
Alloy is AISI 4142
Tempering temperature is in degrees F
![Page 32: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/32.jpg)
Haward Technology Middle East 32Section 8
AWS Certified Welding Inspector (CWI)
Effects of Tempering Temperatures
Alloy contains 12% Cr
Note reduction in impact strength at 885 F (475 C)
![Page 33: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/33.jpg)
Haward Technology Middle East 33Section 8
AWS Certified Welding Inspector (CWI)
Continuous Cooling Diagram & Jominy Hardenability Diagram for 8630 steel. Phase formed on cooling varies with cooling rate.
![Page 34: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/34.jpg)
Haward Technology Middle East 34Section 8
AWS Certified Welding Inspector (CWI)
Weld Area & Fe - Fe3C Diagram
![Page 35: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/35.jpg)
Haward Technology Middle East 35Section 8
AWS Certified Welding Inspector (CWI)
Heat Input
Joules/inch = Current x voltage x 60
Travel speed (in./min)
![Page 36: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/36.jpg)
Haward Technology Middle East 36Section 8
AWS Certified Welding Inspector (CWI)
Preheat
Slows cooling rate
Produces less martensite
Reduces risk of cracking
Reduces distortion
Reduces hydrogen
![Page 37: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/37.jpg)
Haward Technology Middle East 37Section 8
AWS Certified Welding Inspector (CWI)
Carbon Equivalent( CE )
CE = % C + % Mn + % Ni + % Cr + % Cu + % Mo
6 15 5 13 4
![Page 38: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/38.jpg)
Haward Technology Middle East 38Section 8
AWS Certified Welding Inspector (CWI)
Examples of Preheating vs C.E.
C.E. Preheat Temperature
< 0.45 Optional
0.45 - 0.60 200 - 400 °F
>0.60 400 - 700 °F
![Page 39: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/39.jpg)
Haward Technology Middle East 39Section 8
AWS Certified Welding Inspector (CWI)
Heat Treatments for Steels
Super-critical - above transformation temperature
• Annealing
• Normalizing
• Quenching (to harden)
Sub-critical - below transformation temperature
• Tempering
• Stress Relieving
![Page 40: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/40.jpg)
Haward Technology Middle East 40Section 8
AWS Certified Welding Inspector (CWI)
Diffusion
“Movement of atoms within a solution, be it a solid, liquid or gas”
![Page 41: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/41.jpg)
Haward Technology Middle East 41Section 8
AWS Certified Welding Inspector (CWI)
Diffusion of Lead and Gold Atoms
![Page 42: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/42.jpg)
Haward Technology Middle East 42Section 8
AWS Certified Welding Inspector (CWI)
SolubilityDissolving Salt into Water Solid into liquid
Diffusion mechanism
Solubility limit
Temperature effects
![Page 43: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/43.jpg)
Haward Technology Middle East 43Section 8
AWS Certified Welding Inspector (CWI)
Solid Solubility
Unique to metals
Solid into solid
Solubility limit
Temperature effects
![Page 44: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/44.jpg)
Haward Technology Middle East 44Section 8
AWS Certified Welding Inspector (CWI)
Examples of Solid Solubility
Gold and lead bars
Carburizing
Nitriding
![Page 45: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/45.jpg)
Haward Technology Middle East 45Section 8
AWS Certified Welding Inspector (CWI)
Stainless Steels
Ferritic
Martensitic
Austenitic
Precipitation Hardening (PH)
Duplex
![Page 46: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/46.jpg)
Haward Technology Middle East 46Section 8
AWS Certified Welding Inspector (CWI)
Sensitization of Austenitic Alloys
“Formation of chromium carbides between 800 - 1600 °F”
(Sensitization reduces the corrosion resistance in many environments)
![Page 47: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/47.jpg)
Haward Technology Middle East 47Section 8
AWS Certified Welding Inspector (CWI)Corrosion Attack of Austenitic Stainless
Steel
![Page 48: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/48.jpg)
Haward Technology Middle East 48Section 8
AWS Certified Welding Inspector (CWI)
Avoiding Sensitization
Heat treatment ( SAWQ )
Stabilized grades
Low carbon grades
![Page 49: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/49.jpg)
Haward Technology Middle East 49Section 8
AWS Certified Welding Inspector (CWI)
Other Common Alloys
Aluminum
• Pure aluminum
• Aluminum-copper
• Aluminum-magnesium
Copper
• Pure copper
• Brasses
• Bronzes
![Page 50: Section 08 (NXPowerLite).ppt](https://reader036.vdocuments.net/reader036/viewer/2022062314/563dbb5b550346aa9aac7310/html5/thumbnails/50.jpg)
Haward Technology Middle East 50Section 8
AWS Certified Welding Inspector (CWI)
End of this Section