Magnetic Particle Testing Method for Material Inspection

Level I Questions - Magnetic Particle Testing Method Level I Questions Magnetic Particle Testing Method 1. Magnetic particle is a nondestructive testing method used for: Magnetic particles are available in different colors: 5. a. for color contrast with the part surface thereby enhancing detection of indications b. to enhance the detection of indications by allowing background color matching c. to determine if an indication is surface or subsurface d. to indicate different magnetic flux values a. locating surface and near-surface discontinuities in aluminum b. locating surface and near-surface discontinuities in steel c. finding and measuring material separation d. measuring flux density C.2 2. Ferromagnetic material is: C.180 a. strongly attracted by a magnet b. not highly saturated by magnetic fields c. a material with a 0 permeability measurement d. not capable of being magnetized (t ~ Which of the following can be magnetized? 6. a. 1ron b. copper c. aluminum d. magnesium C.380: E.3 3. The permeability of a material describes: a. the ease with which it can be magnetized b. the depth of the magnetic field in the part c. the length of time required to demagnetize it d. the ability to retain the magnetic field C.43 The magnetic field is strongest when: 7. a. the magnetizing voltage is flowing b. the magnetizing current is flowing c. the material exhibits high coercive forces d. the magnetizing current is not flowing C.54 C.385; E.6 4. - 8. The retentivity of a material describes: If a crack exists in a circular magnet, the attraction of magnetic particles to the crack is caused by: a. the ease with which it can be magnetized b. the depth of the magnetic field in the part c. the length of time required to demagnetize it d. the ability to retain the magnetic field a. a coercive force b. a leakage field c. a Doppler effect d. a high reluctance at the crack C.49 C.387; E.4 qg QL eg es Pv es 8('; q]; 1 2 Supplement to Recommended Practice SNT-TC-1A (Q&A Book): Magnetic Particle Testing Method 9. 14. The magnitude of the residual magnetic field in a specimen is dependent on: The unit usually used to denote flux density is: a. b. c. d. a. the length-to-diameter ratio (LID) b. the strength of the applied magnetizing force c. the right-hand rule d. the left-hand rule tesla henry farad ampere C.54 C.54 10. VVhich statement is true when related to magnetic lines of force? 15. a. they are often forced to cross due to part geometry b. they are most dense at the poles of a magnet c. they seek the path of most resistance d. they cannot be detected The proper number of ampere-turns for a given test specimen being examined by longitudinal magnetism is determined by: a. b. c. d. its length and diameter the material the diameter and the material its diameter A.182 C.44 11. Magnetic flux lines that are parallel to a discontinuity produce: a. b. c. d. 16. A circular field may be induced into a specimen by: a. placing the part in an energized coil b. passing current directly through the part c. passing a magnetic field through the part d. placing the part in a north~south orientation strong indications weak indications no indications fuzzy indications C.48 12. A part is adaptable to magnetic particle inspection if: a. b. c. d. it is attached to an electrostatic field the material is ferromagnetic the material is nonferrous the material is an electric conductor C.43 13. What rule describes the direction of current flow ( + to -) when lines of magnetic force surround a conductor? a. b. c. d. C.50 17. An electrical yoke produces: a. b. c. d. a longitudinal field a circular field alternating fields a swinging field C.53: E.27 18. An energized coil around the part produces: left-hand rule right-hand rule flux rule reluctance rule C.50 a. a circular field b. a longitudinal field c. an intermittent field d. a field dependent on the type of current applied C.51; E.9 on • Level I Questions - Magnetic Particle Testing Method 19. In longitudinal magnetization the proper term for calculating magnetizing force is: 23. Which of the following is an advantage of magnetic particle testing over penetrant testing? a. amperes b. ampere-turns c. watts d. ohms A.182 20. Magnetic lines of force: a. b. c. d. travel in straight lines form a closed loop are randomly oriented overlay in highly ferromagnetic materials A.66 C.44; E.4 21. A magnetic particle buildup from a discontinuity is strongest when the discontinuity is oriented: a. b. c. d. a. it does not require post-cleaning of the part b. it requires direct access to the surface of the part c. it can detect near-surface discontinuities d. it requires a shorter dwell time to produce results 24. The amount of amperage used for magnetic particle inspection using the prod metho_d is determined from the: a. type of material b. distance between the prods c. diameter of the part d. total length of the part 180 degrees to the magnetic flux flow 45 degrees to the magnetic flux flow 90 degrees to the magnetic flux flow 90 degrees to the current flow C.48 22. A specimen may be demagnetized by which of the following methods? a. heat treatment below the curie temperature b. placing the part in an alternating current coil c. placing the part in reversing and decreasing direct current fields d. applying a direct current yoke and removing it from the part A.66; E.54 C.113 25. The flux within and surrounding a magnetized part or around a conductor carrying a current is known as: a. b. c. d. the saturation point a magnetic field the ferromagnetic field the paramagnetic field C.112 26. The areas on a magnetized part from which the magnetic field is leaving or returning into the part are called: a. salient points b. defects c. magnetic poles d. nodes C.44 27. A metal that is difficult to magnetize is said to have: a. b. c. d. high permeability low permeability low coercive force low retentivity C.56; E.44 qu; qg(; QQ(; 3 4 Supplement to Recommended Practice SNT-TC-1A (Q&A Book): Magnetic Particle Testing Method 28. The magnetism that remains in a piece of magnetizable material after the magnetizing force has been removed is called the: a. b. c. d. 33. Inspecting a part by magnetizing, removing the current flow, then applying the medium is called the: a. b. c. d. tramp magnetism residual magnetism damped magnetism permanent magnetism continuous method wet method residual method dry method C.63 C. 54 34. 29. Subsurface discontinuity indications usually appear: a. b. c. d. sharp and distinct sharp and wide wide and fuzzy high and loosely held a. dry residual method using DC with surge b. wet continuous method using half-wave rectified current c. wet residual method d. dry continuous method using half-wave rectified current with prods 0.35 30. Which residual field is most difficult to demagnetize? a. b. c. d. longitudinal circular vector binodal C.i17 35. C.281 31. Which magnetic particle application technique is the most sensitive? a. b. c. d. A curve is sometimes drawn to show graphically the relation of the magnetizing force to the strength of the magnetic field produced in a certain material. This curve is known as the: a. b. c. d. continuous residual interrupted counter-current magnetic force curve hysteresis curve saturation curve induction curve C.54; E.6 36. C.64 32. Which of the following is the most effective method for the detection of near-surface defects? Fluorescent magnetic particle indications should be inspected under: What method of applying particles provides greater sensitivity in locating subsurface weld discontinuities? a. continuous b. residual a. any light c. circular d. longitudinal b. a neon light c. an ultraviolet light d. a fluorescent light C.180 C.62; E.39 89£ Pt£ 0££ qQ£ 06(': qgc: