NDT 103 - Magnetic Particle Testing (MT) Level I and II

3 Credits, 3 Contact Hours
3 lecture periods 0 lab periods
Provides accurate, current and thorough training that leads directly to the ability of the student to perform valid magnetic particle inspection. Level I and II material is combined and presented in a single classroom course. Includes the basic knowledge of magnetic particle inspection, magnetic properties, and the basic theory of magnetism and its many applications for the testing of ferromagnetic materials. Also includes the use of yoke, and wet bench applications, the proper use and calibration of media and equipment, and an overview of the origin and nature of discontinuities.

Prerequisite(s): NDT 100  
  

1. Demonstrate proficient knowledge of magnetic particle testing.
2. Demonstrate proficient knowledge of the use of magnetic particle equipment.
3. Demonstrate proficient knowledge of how to set up and calibrate NDT equipment.
4. Demonstrate proficient knowledge and a basic understanding of magnetism.

1. Magnetic Domain Theory
   1. Properties of a magnet
   2. Magnetic field
   3. Flux leakage
2. Magnetizing Ferromagnetic Materials
   1. Magnetic flow
   2. Current flow
   3. Magnetic properties of materials
   4. Formation of a hysteresis loop
3. Method of Magnetization
4. Circular magnetization current flow
5. Threader bar
6. Longitudinal magnetization
7. Coil quick break technique
8. Magnetic flow induced current magnetization
9. Overall method
10. Detecting Media
    1. General –properties of magnetic particle
    2. Materials
    3. Dry powders
    4. Magnetic inks – Preparation and use of inks, particle content checks, standard test pieces
    5. Comparison of wet and dry methods – Advantages of wet and dry methods
    6. Magnetic rubber inspection – MRI paint process
11. Equipment
    1. Swinging field system
    2. Coils
    3. Threader bars
    4. Field indicators
    5. Inks and ink applicators
    6. Flux indicators
    7. Particle content testing kit
    8. Gauss meter
    9. Ketos ring
12. Demagnetization
    1. Demagnetization methods
    2. Aperture type coil
    3. Aperture type coil with variable current
    4. AC Yokes
    5. Diminishing AC flow
    6. Reversing DC
    7. Heat treatment
13. Practical Procedures
    1. Wet continuous – Dry continuous
    2. Wet residual – Dry residual
    3. Surface preparation
    4. Initial demagnetization
    5. Degreasing and cleaning
    6. Technique application
    7. Inking
    8. Magnetization
    9. Viewing
    10. Marking indications
    11. Assessment and recording flaws
    12. Demagnetization
    13. Cleaning
    14. Surface protection
14. Interpretations of Indications
    1. Defect indications
    2. Viewing conditions – Visual acuity, experience, relevant indications, non-relevant indications
    3. False indications
    4. Spurious indications
    5. Flux leakage due to geometry
    6. Changes in permeability
    7. Magnetic writing
    8. Confirmation of indications
15. Assessing Amperage
    1. Current flow
    2. Threader bar
    3. Coil
    4. Extenders
    5. Prods
    6. Meter readings and current flow for various waveforms
16. Inspection Standards and Codes
    1. ASTM and ASME standards
    2. Minimum requirements
    3. Acceptance and rejection criteria