Today's KNOWLEDGE Share: 𝐖𝐡𝐲 𝐝𝐨 𝐰𝐞𝐥𝐝𝐬 𝐜𝐫𝐚𝐜𝐤?

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Today's KNOWLEDGE Share:

𝐖𝐡𝐲 𝐝𝐨 𝐰𝐞𝐥𝐝𝐬 𝐜𝐫𝐚𝐜𝐤?

- 𝗔 𝘄𝗲𝗹𝗱𝗶𝗻𝗴 𝗰𝗿𝗮𝗰𝗸 is fracture-type linear imperfection having a sharp tip with a higher length and very small width.

- Welding cracks can appear in weld deposits, heat-affected zones (HAZ), and base material.




- They occur once the localized stresses exceed the ultimate tensile strength of the base metal.

- 𝗜𝗻𝗶𝘁𝗶𝗮𝗹 𝗖𝗿𝗮𝗰𝗸𝗶𝗻𝗴 usually starts at stress concentrations due to other defects or sharp notches (notches work as stress concentration) in the nearby area.

- These stresses can be residual stresses caused by the welding or stresses applied due to service or other external loading.


- 𝗥𝗲𝘀𝗶𝗱𝘂𝗮𝗹 𝘀𝘁𝗿𝗲𝘀𝘀𝗲𝘀 in welding are caused by weld solidification and thermal expansion properties of the metal.

- In welding cracks, there is little plastic deformation as most of the cracks either occur due to high hardness or Stress.


Sources:weldguru.com/www.materialwelding.com

Visit MY BLOG http://polymerguru.blogspot.com


#weldinginspection #metals  #welding #cracking #asme  #weldingengineer #metallurgy #piping

#tensile  

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