1. Scope 1.1 This guide describes techniques for both dry and wet magnetic particle examination, a nondestructive method for detecting cracks and other discontinuities at or near the surface in ferromagnetic materials. Magnetic particle examination may be applied to raw material, semifinished material (billets, blooms, castings, and forgings), finished material and welds, regardless of heat treatment or lack thereof. It is useful for preventive maintenance examination. 1.1.1 This guide is intended as a reference to aid in the preparation of specifications/standards, procedures and techniques. 1.2 This guide is also a reference that may be used as follows: 1.2.1 To establish a means by which magnetic particle examination, procedures recommended or required by individual organizations, can be reviewed to evaluate their applicability and completeness. 1.2.2 To aid in the organization of the facilities and personnel concerned in magnetic particle examination. 1.2.3 To aid in the preparation of procedures dealing with the examination of materials and parts. This guide describes magnetic particle examination techniques that are recommended for a great variety of sizes and shapes of ferromagnetic materials and widely varying examination requirements. Since there are many acceptable differences in both procedure and technique, the explicit requirements should be covered by a written procedure (see Section 21). 1.3 This guide does not indicate, suggest, or specify acceptance standards for parts/pieces examined by these techniques. It should be pointed out, however, that after indications have been produced, they must be interpreted or classified and then evaluated. For this purpose there should be a separate code, specification, or a specific agreement to define the type, size, location, degree of alignment and spacing, area concentration, and orientation of indications that are unacceptable in a specific part versus those which need not be removed before part acceptance. Conditions where rework or repair are not permitted should be specified. 1.4 This guide describes the use of the following magnetic particle method techniques. 1.4.1 Dry magnetic powder (see 8.3), 1.4.2 Wet magnetic particle (see 8.4), 1.4.3 Magnetic slurry/paint magnetic particle (see 8.4.8), and 1.4.4 Polymer magnetic particle (see 8.4.8). 1.5 Personnel Qualification -Personnel performing examination to this guide shall be qualified and certified in accordance with ASNT Qualification and Certification of NDT Personnel, or SNT-TC-1A, or MIL-STD-410 for military purposes, or as specified in the contract or purchase order. 1.6 Nondestructive Testing Agency -If a nondestructive testing agency as described in Practice E543 is used to perform the examination, the testing agency shall meet the requirements of Practice E543. 1.7 Table of Contents: SECTION Scope 1 Scope Description 1.1 A Reference Document 1.2 Acceptance Standards for Parts not Covered 1.3 Magnetic Particle Method Techniques 1.4 Personnel Qualifications 1.5 Nondestructive Testing Agency 1.6 Table of Contents 1.7 SI Units 1.8 Safety Caveat 1.9 Referenced Documents 2 ASTM Standards 2.1 SAE Documents 2.2 ASNT Documents 2.3 U.S. Government Documents 2.4 Definitions 3 Summary of Guide 4 Principle 4.1 Method 4.2 Magnetization 4.3 Types of Magnetic Particle and Their Use 4.4 Evaluation of Indications 4.5 Typical Magnetic Particle Indications 4.6 Significance and Use 5 Equipment 6 Types 6.1 Portability 6.2 Yokes 6.3 Prods 6.4 Black Light 6.5 Equipment Verification 6.6 Examination Area 7 Light Intensity for Examination 7.1 Housekeeping 7.2 Magnetic Particle Materials 8 Particle Types 8.1 Particle Characteristics 8.2 Dry Particles 8.3 Wet Particle Systems 8.4 Part Preparation 9 General 9.1 Cleaning Examination Surface 9.2 Sequence of Operations 10 Sequencing Particle Application and Establishing 10.1 Magnetic Flux Field Types of Magnetizing Currents 11 Basic Current Types 11.1 Part Magnetization Techniques 12 Examination Coverage 12.1 Direct and Indirect Magnetization 12.2 Choosing a Magnetization Technique 12.3 Direction of Magnetic Fields 13 Discontinuity Orientation vs Magnetic Field Direction 13.1 Circular Magnetization 13.2 Torodial Magnetization 13.3 Longitudinal Magnetization 13.4 Multidirectional Magnetization 13.5 Magnetic Field Strength 14 Magnetizing Field Strengths 14.1 Establishing Field Strengths 14.2 Guidelines for Establishing Magnetic Fields 14.3 Application of Dry and Wet Magnetic Particles 15 Dry Magnetic Particles 15.1 Wet Particles Applications 15.2 Magnetic Slurry/Paint 15.3 Magnetic Polymers 15.4 Interpretation of Indications 16 Valid Indications 16.1 Recording of Indications 17 Means of Recording 17.1 Accompanying Information 17.2 Demagnetization 18 Applicability 18.1 Demagnetization Methods 18.2 Extent of Demagnetization 18.3 Post Examination Cleaning 19 Particle Removal 19.1 Means of Particle Removal 19.2 Evaluation of System Performance/Sensitivity 20 Contributor Factors 20.1 Maintenance and Calibration of Equipment 20.2 Equipment Checks 20.3 Examination Area Light Level Control 20.4 Dry Particle Quality Control Tests 20.5 Wet Particle Quality Control Tests 20.6 Bath Characteristics Control 20.7 Verifying System Performance 20.8 Procedure and Report 21 Written Procedure 21.1 Written Reports 21.2 Acceptance Standards 22 Safety 23 Precision and Bias 24 Keywords 25 Annex 1.8 The numerical values shown in inch-pound units are to be regarded as the standard. SI units are provided for information only. 1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.