Magnetic particle inspection is an inspection method used to identify defects on the surface of ferromagnetic materials by running a magnetic current through it. It can also be used to detect defects just beneath the surface of materials.

1. A Brief Presentation On
Magnetic Particle Testing
By
Hemanth Kumar J
MTech(Manufacturing Engineering) Student,
School of Mechanical Engineering(SMEC),
Vellore Institute of Technology, Vellore Campus, TN, India-632014

2. A Brief Presentation On Magnetic Particle Testing
Outline of the Presentation
1. What is Magnetic Particle Testing ?
2. Basic Theory of Magnetism
3. How Does Magnetic Particle Testing Work?
4. Magnetic Particle Testing Standards
5. Types of Magnetic Particle Testing
6. Steps Involved In Dry And Wet Particle Testing
7. Magnetization Methods
8. Magnetic Field Indicators
9. Types of Particles Used In Magnetic Particle Testing
10. Applications
11. Advantages & Limitations of Magnetic Particle Testing

3. A Brief Presentation On Magnetic Particle Testing
What is Magnetic Particle Testing?
Magnetic particle inspection is
an inspection method used to
identify defects on the surface
of ferromagnetic materials by
running a magnetic current
through it. It can also be used
to detect defects just beneath
the surface of materials.

4. A Brief Presentation On Magnetic Particle Testing
Basic Theory of Magnetism

5. A Brief Presentation On Magnetic Particle Testing
How Does Magnetic Particle Testing Work?

6. A Brief Presentation On Magnetic Particle Testing
Magnetic Particle Testing Standards
The various magnetic testing standards used globally are as follows:
1. ISO 9934-1:2016 specifies the surface preparation of the part to be tested, magnetization
techniques, requirements and application of the detection media, and the recording and
interpretation of results.
2. ASTM E709-19 is used as a base standard for all magnetic particle testing methods in all
industries.
3. ASTM E1444 is a standard used only for the magnetic particle testing in the aerospace
industries.
4. ASTM E3024 establishes minimum requirements for magnetic particle testing used for the
detection of surface or slightly subsurface discontinuities in ferromagnetic material.

7. A Brief Presentation On Magnetic Particle Testing
Types of Magnetic Particle Testing
Dry Particle Inspection Wet Particle Inspection

8. A Brief Presentation On Magnetic Particle Testing
Steps Involved In Dry
Particle Testing.
1. Prepare the part surface
2. Apply the magnetizing force
3. Dust on the dry magnetic particles
4. Blow off excess magnetic particles
5. Terminate the magnetizing force
6. Inspect for indications
Steps Involved In Wet Particle
Testing
1. Prepare the surface
2. Apply the suspension
3. Apply the magnetizing force
4. Inspect for indications

9. A Brief Presentation On Magnetic Particle Testing
Magnetization Methods
Prod Technique
Longitudinal magnetization
technique
Circular Magnetization
Technique

10. A Brief Presentation On Magnetic Particle Testing
Magnetization Methods
Yoke Technique Multidirectional Magnetization Technique

11. A Brief Presentation On Magnetic Particle Testing
Magnetic Field Indicators
1. Determining whether a magnetic field is of adequate strength and in the proper direction is critical
when performing magnetic particle testing.
2. Knowing the direction of the field is important because the field should be as close to perpendicular to
the defect as possible and no more than 45 degrees from normal.
3. Being able to evaluate the field direction and strength is especially important when inspecting with a
multidirectional machine, because when the fields are not balanced properly, a vector field will be
produced that may not detect some defects.
4. The various indicators are as follows:
a. Ketos Ring
b. Gauss Meter
c. Quantitative Quality Indicator (QQI)
d. Pie Gage

12. A Brief Presentation On Magnetic Particle Testing
Magnetic Field Indicators(Cont)
Ketos Ring
Gauss Meter

13. A Brief Presentation On Magnetic Particle Testing
Magnetic Field Indicators(Cont.)
Quantitative Quality Indicator (QQI)
Pie Gage

14. A Brief Presentation On Magnetic Particle Testing
Types of Particles Used In Magnetic Particle Testing
Dry Particles Wet Particles

15. A Brief Presentation On Magnetic Particle Testing
Applications
Crankshaft Inspection Underwater Weld Inspection

16. A Brief Presentation On Magnetic Particle Testing
Applications(Cont.)
Weldment Inspection Boiler Weld Inspection

17. A Brief Presentation On Magnetic Particle Testing
Advantages & Limitations of Magnetic Particle Testing
Advantages Limitations
Simple to use Surface/ Subsurface detection only
Inexpensive Only suitable for magnetic materials
Rapid results No indication of defect depths
Little surface preparation Detection is needed in two directions
More sensitive than visual inspection

18. A Brief Presentation On Magnetic Particle Testing
References
1. https://www.nde-ed.org/NDETechniques/MagParticle/Equipment/Particles.xhtml
2. https://www.nationalboard.org/index.aspx?pageID=164&ID=377
3. https://www.sisco.kobelco.com/english/service/nondestructiveness/mt.html