How can eddy current be used in NDT?

Eddy current testing is a non-destructive testing (NDT) inspection method used for a variety of purposes, including for flaw detection, material and coating thickness measurements, material identification and establishing the heat treatment condition of certain materials.

What is eddy current testing used for?

Eddy current testing is most commonly used to inspect surfaces and tubes. It is an incredibly sensitive testing method, and can identify even very small flaws or cracks in a surface or just beneath it. On surfaces, ETC can be done with both ferromagnetic and non-ferromagnetic materials.

What is eddy current crack detection?

Eddy current testing The eddy current testing is a non destructive test method for conductive materials to detect surface defects like cracks, pores or inclusions. For this, a probe is moved contactless over the test part.

What are the instruments used in eddy current testing?

Eddy Current Testing Instruments for Manufacturing

• NDT Instruments.
• Ultrasound.
• Eddy Current. ECT Instrumentation. MIZ-21C. MIZ-200. MIZ-85iD. MIZ-28. MIZ-21B. InSite HT & CT. ET Software. ET Probes.
• Mechanical Systems.

How does an eddy current separator work?

Eddy current separators remove nonferrous metals such as aluminum, die-cast metal, and copper from nonmetallic material. Material is fed onto the conveyor belt of the separator, which moves it across the magnetic rotor where separation occurs.

What is the basic principle of eddy current testing?

Eddy current testing uses the principle of electromagnetic induction to detect flaws in conductive materials. An excitation coil carrying current is placed in proximity to the component to be inspected.

What kind of defects can be detected by eddy current testing method?

The Eddy current technology lends itself well to the detection of near-surface or surface breaking defects such as surface scratches and corrosion and distinguishes types of conductive materials.

What are the materials equipment used in eddy current?

They are used to detect flaws, determine thickness, inspect welds, measure conductivity, and sort alloys. Eddy current instruments include a straight or angled magnetic probe and an analog or digital meter with a zero reference point.

How eddy currents are produced?

When a conductor travels through a magnetic field or when the magnetic field around a stationary conductor changes, eddy currents are produced. Eddy currents can thus be generated anytime the intensity or direction of a magnetic field changes in a conductor.

How do you separate ferrous and nonferrous metals?

Powerful magnets separate the magnetic metals from nonferrous metals. Metals may be sorted further and are then shredded or sheared into smaller pieces. More magnets separate out any smaller pieces of ferrous metals. From there, the pieces may be melted and formed into new shapes, or baled into large blocks.

What are the disadvantages of eddy currents?

Disadvantages of Eddy Currents: There is a major heat loss during cycling eddy currents due to friction in the magnetic circuit, especially where the core is saturated. Thus there is the loss of useful electrical energy in the form of heat. There is magnetic flux leakage.

What is the advantage of eddy current?

The two advantages of eddy current in practical applications are: Sensitivity to surface defects: Able to detect defects of 0.5mm in length under favourable conditions. Accurate conductivity measurements: Dedicated conductivity measurement instruments operate using eddy currents.

What kind of materials can be checked and tested with an eddy current tester?

The technology is now widely used in the aerospace, automotive, petrochemical, and power generation industries for the detection of surface or near-surface defects in materials such as aluminum, stainless steel, copper, titanium, brass, Inconel®, and even carbon steel (surface defects only).

What is difference between ferrous and non-ferrous?

The difference between ferrous and non-ferrous metals is that ferrous metals contain iron and non-ferrous metals do not. This basic difference imparts distinctive properties on the two types of metals, which add to their own personal physical properties and determine the applications they are most suited for.