Magnetic Particle Inspection (MPI)
Magnetic particle inspection, also called MT or magnetic particle testing, uses a magnetic field and particles to reveal surface and some near-surface discontinuities.
Overview
Magnetic particle inspection, also called MT or magnetic particle testing, uses a magnetic field and particles to reveal surface and some near-surface discontinuities.
NDT Australia provides a single enquiry and co-ordination point for industrial inspection through specialist partners. The proposed provider, personnel competence, method-specific qualifications where required, insurance and any separate approval requirements are checked for the actual scope before appointment; no general accreditation or acceptance guarantee is implied.
Assets & Materials
Ferromagnetic steel welds, castings, forgings and selected lifting or machinery components are candidates. Aluminium and most austenitic stainless steels need a different method.
Methods & Limitations
Magnetisation direction, surface preparation, particle system and viewing conditions are selected for the examination. More than one field direction may be needed to address likely crack orientations.
MPI is principally a surface method, not a view through an entire weld. Paint, rough profiles and geometry can reduce sensitivity or produce non-relevant indications; cleaning and demagnetisation requirements are agreed where needed.
Typical Defects & Conditions
- Surface-breaking fatigue cracks in selected steel welds
- Crack-like indications at stress concentrations
- Accessible repair-area discontinuities after preparation
Planning the Inspection
Identify material, access, coating removal restrictions and the areas of concern. Include a repair history so the inspection can distinguish a new response from an already documented location.
Expected Reporting Deliverables
Expect component or weld references, technique and field arrangement, examination extent, indication locations, evaluation criteria and any preparation or viewing limitations.
Relevant Industries & Practical Guides
construction inspection planning
manufacturing inspection planning
Applications
Magnetic Particle Inspection is applied across a wide range of assets and industries, including:
- Ferromagnetic steel welds, castings, forgings and selected lifting or machinery components are candidates. Aluminium and most austenitic stainless steels need a different method.
- Inspection planning for construction assets and operators
- Inspection planning for mining assets and operators
- Inspection planning for manufacturing assets and operators
Standards & Competence Context
The references below are planning context, not a claim of accreditation, certified compliance or a universal acceptance rule. Confirm the applicable edition, part, material, procedure and acceptance criteria for this asset. Verify the appointed personnel's method, level and sector competence, insurance and any engineering authority required for the scope before work. A method standard is not itself a return-to-service approval.
- AS 1171 — Magnetic particle testing of ferromagnetic products
- ISO 9934 — Magnetic particle testing general principles
Why Choose NDT Australia
- One enquiry point for scope and specialist-partner co-ordination
- Asset-linked findings with examination extent and limitations
- Separate identification of engineering and operational decisions
Frequently Asked Questions
Related Services
Explore complementary inspection scopes. Method, specialist partner and availability are confirmed for the asset and location.