## Duration: 10 days

## What will I learn?

This curriculum meets or exceeds the examination

syllabus for the certification of Level 2 personnel in Eddy

Current Testing of Aerospace Materials and

Components, in accordance with EN 4179.

The course ends with the certification examination.

**Objectives**

**Day 1 (Hours 1 to 4) THEORY, CHAPTER 1: Basic **

**Principles of Eddy Currents**

Applications, Advantages, Limitations, Eddy currents,

alternating current in a coil, Magnetic coupling,

Production of eddy currents, Lenz’s Law, eddy

current inspection, Calibration of high frequency meter

instruments, Inspection using high frequency meter

instruments, Calibration of high frequency phase

display instruments, Inspection using high frequency

phase display instruments

**CHAPTER 2: Factors affecting Eddy Currents**

Conductivity, Permeability, Ferrous, non-ferrous,

paramagnetic and diamagnetic materials, Frequency,

Geometry, Proximity, Discontinuities, Probe handling,

Depth of penetration

APPENDIX B: Reference Literature: Standards and

Specifications

APPENDIX E: Glossary of Terms

HOMEWORK Chapters 1 & 2 issued

**Day 2 (Hours 9 to 12) THEORY,**

Review of Homework Chapters 1 & 2

**CHAPTER 3: Electrical Theory**

Direct current (DC), Direct current theory, Alternating

current (AC) theory

**Day 2 (Hours 13 to 16) PRACTICAL,**

Hours 13 to 16 Student Practice Impedance, Bridge

Instrument Conductivity Meter

Practical Exercises (QRS 29) HOMEWORK Chapter 3

issued

**Day 3 (Hours 17 to 20) THEORY**

Review of Homework Chapter 3

**CHAPTER 4: Phase Analysis**

Current/Voltage phase relationship, Conductivity

changes, Dimensional changes Change in frequency,

Change in permeability, Changes in probes, Choice of

operating point and f/fg, Characteristic frequency

**Day 3 (Hours 21 to 24) PRACTICAL,**

Hour 21 Instructor Demo, Impedance Plane Instrument

High Frequency Application Hours 22 to 24 Student

Practice, Impedance Plane Instrument High Frequency

Application Practical Exercises

HOMEWORK Chapter 4 issued

**Day 4 (Hours 25 to 28) THEORY,**

Review of Homework Chapter 4

Review of Chapter 4: Phase Analysis

**CHAPTER 5: Practical Impedance Plane Analysis**

Reviewing impedance plane fundamentals

Presentation of conductivity, Lift-Off (coating thickness

measurement) Selection of frequency, Corrosion and

cracks in subsurface layers Location of 2nd layer

corrosion or cracking Change of probe, Change of

permeability

**Day 4 (Hours 29 to 32) PRACTICAL,**

Hour 29 Instructor Demo Impedance Plane Instrument

Conductivity Measurement

Hours 30 to 32 Student Practice Impedance Plane

Instrument High Frequency Application

Conductivity Measurement Practical Exercises

HOMEWORK Chapters 5 issued

Day 5 (Hours 33 to 36) THEORY,

Review of Homework Chapter 5

**CHAPTER 6: Coils and Probes**

Surface coils, High frequency surface probes Low

frequency surface probes, encircling coils, Internal coils,

Fill factor, Coil magnetic fields Ferrite core probes Air

core probes Shielded

coil probes Saturation probes, Factors effecting eddy

current probe performance

**CHAPTER 7: Coil Arrangement**

Single absolute coil, Double absolute coil, Single

differential coil, Double differential coil, Selfcomparative system, External comparative system

**Day 5 (Hours 37 to 40) PRACTICAL,**

Hour 37 Instructor Demo, Impedance Plane Instrument

Differential Coils High Frequency

Application

Hours 38 to 40 Student Practice, Impedance Plane

Instrument High Frequency Application

Differential Coils

Practical Exercises

HOMEWORK Chapters 6 & 7 issued

**Day 6 (Hours 41 to 44) THEORY,**

Review of Homework Chapters 6 & 7

Review of Days 1 to 5

**CHAPTER 8: Practical Eddy Currents**

High frequency crack detectors (surface faults), Hole

inspection, Low frequency tests sets

(variable frequency), Corrosion detection-subsurface,

Crack detection-subsurface

**Day 6 (Hours 45 to 48) PRACTICAL,**

Hour 45 to 46 Instructor Demo, Impedance Plane

Instrument Low Frequency Application

Corrosion Detection-subsurface Crack Detectionsubsurface

Hours 47 to 48 Student Practice, Impedance Plane

Instrument Low Frequency Application

Corrosion Detection-subsurface Crack Detectionsubsurface Practical Exercises

HOMEWORK Chapter 8 issued.

**Day 7 (Hours 49 to 52) THEORY,**

Review of Homework Chapter 8

APPENDIX A: Writing of Reports and Instructions

**Day 7 (Hours 53 to 56) PRACTICAL,**

Hours 53 to 56 Student Practice Writing of a report and

an instruction Practical Exercises

**Day 8 (Hours 57 to 60) THEORY,**

Review of Reports and Instructions

**CHAPTER 9: Use of Filters**

Modulation, Eddy current instrument filter usage,

Filters, Selection of frequency

CHAPTER 10: Bolt and Fastener Hole Inspection using

Rotating ‘Spinning’ Probe

Equipment, Advantages, Probes, displays – time-base

and spot, Interpretation, Effect of frequency,

Calibration blocks, Calibration, Inspection, Spinning

probes

**Day 8 (Hours 61 to 64) PRACTICAL,**

Hour 61 to 62 Instructor Demo, Impedance Plane

Instrument Use of Filters Bolt and

Fastener Hole Inspection

Hours 63 to 64 Student Practice, Impedance Plane

Instrument Use of Filters Bolt and

Fastener Hole Inspection

Practical Exercises

HOMEWORK Chapters 9 & 10 issuedDay 9 (Hours 65 to 68) THEORY,

Review of Homework Chapters 9 & 10

**CHAPTER 11: Dual Frequency Inspection**

Overview of dual frequency inspection Reference

standard, Principle of dual frequency calibration, Choice

of Frequency 1 and Frequency 2, Practical calibration

CHAPTER 12: Basic Test Set Design

Bridge circuits, Bridge circuits with resonant probes

pure impedance measuring circuits Phase comparison

circuits, warning devices, Impedance plane analysis

display instruments, Cathode Ray Tube.

**Day 9 (Hours 69 to 72) PRACTICAL,**

Hour 69 Instructor Demo, Impedance Plane Instrument

Dual Frequency Calibration Dual

Frequency Inspection

Hours 70 to 72 Student Practice, Impedance Plane

Instrument Dual Frequency Calibration

Dual Frequency Inspection Practical Exercises

HOMEWORK Chapters 11 & 12 issued

**Day 10 (Hours 73 to 80) THEORY,**

Review of Homework Chapters 11 & 12

Review of Days 6 to 9

APPENDIX C: Comparison of Methods

Course Review Theory Review Practical Review

End of Course Examination

**Day 10 (Hours 73 to 80) PRACTICAL,**

Hours 73 to 80 Student Practice, Impedance Plane

Instrument Completion of Exercises as required

Practical Exercises