xiii
Magnetic Particle Testing Procedure .....................................................31
Testing Techniques .....................................................................32
Magnetic Field Theory ..................................................................32
Magnetic Domains .................................................................32
Magnetic Poles ....................................................................32
Magnetic Fields ....................................................................33
Magnetized Ring ...................................................................33
Bar Magnet .......................................................................33
Retentivity and Coercive Force ......................................................33
Effect of Materials on Electromagnetic Fields ..............................................33
Units of Measure for Magnetic Flux ....................................................34
Magnetic Hysteresis ................................................................34
Magnetic Field Strength and Flux Density ...........................................34
Removal of Residual Magnetism ..................................................34
Residual Magnetism and Heat-Treatment ...........................................34
Magnetic Permeability ..............................................................35
Lesson 7 Quiz .........................................................................37
Lesson 8: Flux Fields ....................................................................39
Electric Current ........................................................................39
Alternating Current .................................................................39
Safety Precautions ..............................................................39
Direct Current .....................................................................39
Half-Wave Current ..............................................................40
Single-Phase Full-Wave Current ...................................................40
Three-Phase Full-Wave Current ....................................................41
Voltage and Current Factors ............................................................41
Lesson 8 Quiz .........................................................................43
Lesson 9: Magnetic Particles and Methods of Application ...................................45
Introduction ..........................................................................45
Particle Size .......................................................................45
Dry versus Wet Applications ..........................................................45
Use of Wetting Agents ...........................................................45
Dry Applicators .................................................................46
Current Level and Particle Application ................................................46
Selection of Magnetization Method ......................................................46
Continuous Method ....................................................................46
Continuous Wet Method Procedure ...................................................47
Magnetizing Current with the Continuous Method ......................................47
Residual Method ......................................................................47
Residual Method Amperage .........................................................47
Residual Wet Method Procedure .....................................................48
Use of Dry Powders with the Residual Method ..........................................48
Magnetic Particle Testing Procedure .....................................................31
Testing Techniques .....................................................................32
Magnetic Field Theory ..................................................................32
Magnetic Domains .................................................................32
Magnetic Poles ....................................................................32
Magnetic Fields ....................................................................33
Magnetized Ring ...................................................................33
Bar Magnet .......................................................................33
Retentivity and Coercive Force ......................................................33
Effect of Materials on Electromagnetic Fields ..............................................33
Units of Measure for Magnetic Flux ....................................................34
Magnetic Hysteresis ................................................................34
Magnetic Field Strength and Flux Density ...........................................34
Removal of Residual Magnetism ..................................................34
Residual Magnetism and Heat-Treatment ...........................................34
Magnetic Permeability ..............................................................35
Lesson 7 Quiz .........................................................................37
Lesson 8: Flux Fields ....................................................................39
Electric Current ........................................................................39
Alternating Current .................................................................39
Safety Precautions ..............................................................39
Direct Current .....................................................................39
Half-Wave Current ..............................................................40
Single-Phase Full-Wave Current ...................................................40
Three-Phase Full-Wave Current ....................................................41
Voltage and Current Factors ............................................................41
Lesson 8 Quiz .........................................................................43
Lesson 9: Magnetic Particles and Methods of Application ...................................45
Introduction ..........................................................................45
Particle Size .......................................................................45
Dry versus Wet Applications ..........................................................45
Use of Wetting Agents ...........................................................45
Dry Applicators .................................................................46
Current Level and Particle Application ................................................46
Selection of Magnetization Method ......................................................46
Continuous Method ....................................................................46
Continuous Wet Method Procedure ...................................................47
Magnetizing Current with the Continuous Method ......................................47
Residual Method ......................................................................47
Residual Method Amperage .........................................................47
Residual Wet Method Procedure .....................................................48
Use of Dry Powders with the Residual Method ..........................................48