DESTRUCTIVE TESTING WELDING

DESTRUCTIVE TESTING WELDING

1. HARDNESS: The ability of material to resist Indentation. It is effected by adding carbon.
2. TOUGHNESS:  The ability of material to absorb Impact Energy. It is effected by adding manganese
3. TENSILE STRENGTH:  The ability of material to resist Pulling Force.
4. DUCTILITY:  the ability of material to deform plasticity under tension.
5. Destructive Testing is divided into two categories.
6. QUALITATIVE TESTS.(include: Macro Test, Fracture Test & Nick Break Test)
7. QUANTITATIVE TESTS.(include: Hardness Test, Tensile Test, Toughness Test & C.T.O.D Test)
8. Quantitative test measures Mechanical Properties and have Units
9. Qualitative test doesn’t measure Mechanical Properties and don’t have Units.
10. Transverse tensile test is done to measure Tensile Strength of Joint.
11. All Weld Tensile Test is done by Electrode Manufacturers to measure Tensile Strength, Yield Strength (or) Proof Strength and Tensile Ductility.
12. Tensile Test Specimens gauge length should be 100% weldable.
13. Charpy Impact test is done to measure Toughness and Units are Joules.
14. If Fracture Surface is flat and Featureless then it is Brittle Fracture.
15. If  Fracture Surface is rough and torn then it is Ductile Fracture.
16. If  Fracture Surface is Smooth then it is Fatigue Fracture.
17. CRACK TIP OPENING DISPLACEMENT TEST (CTOD TEST) is done to measure Fracture Toughness & units is “mm”.
18. If Thickness is,                                                                                                                                                                                                           Below 12mm →  Face Bend Test or Root Bend Test can be done.                                                                                                   Above 12mm →  Side bend Test should be done.
19. Butt Fracture Test is also called as “NICK BREAK TEST”.
20. Macro means 10 times magnification (x10) & inspection must be done before & after etching.
21. Charpy  Test  can be used to measure the toughness of weld metal, HAZ, & parent material.
22. The bend test in which the face is in tension & root is in compression is called Face Bend Test.
23. Titanium is added to avoid Weld Decay.
24. Molybdenum is added to avoid Creep.
25. Midway temperature between ductile fracture & brittle fracture is Trasition Temperature.
26. HARDNESS TESTING:

1. 1. Vicker Diamond Pyramid: Uses Diamond Indentor
   2. Brinells Hardness Test: Uses Steel Ball Indentor
   3. Rockwell Hardness Test: Uses both indentor.