Editing Nondestructive testing (section)

==Methods and techniques==
[[Image:Replica system for nondestructive testing.JPG|thumb|right|An example of a 3D replicating technique. The flexible high-resolution replicas allow surfaces to be examined and measured under laboratory conditions. A replica can be taken from all solid materials.]]

NDT is divided into various ''methods'' of nondestructive testing, each based on a particular scientific principle. These methods may be further subdivided into various ''techniques''. The various methods and techniques, due to their particular natures, may lend themselves especially well to certain applications and be of little or no value at all in other applications. Therefore, choosing the right method and technique is an important part of the performance of NDT.

*[[Acoustic emission]] testing (AE or AT)
*[[Acoustic microscopy]]
*[[Blue etch anodize]] (BEA)
*[[Dye penetrant inspection]] or liquid penetrant testing (PT or LPI)
*[[Electromagnetic testing]] (ET) or electromagnetic inspection (commonly known as "EMI")
**[[Alternating current field measurement]] (ACFM)
**[[Alternating current potential drop measurement]]  (ACPD)
**[[Barkhausen effect|Barkhausen]] testing
**[[Direct current potential drop measurement]]  (DCPD)
**[[Eddy-current testing]] (ECT)
**[[Magnetic flux leakage]] testing (MFL) for pipelines, tank floors, and wire rope
**[[Magnetic-particle inspection]] (MT or MPI)
**[[Magnetovision]]
**[[Remote field testing]] (RFT)
*[[Ellipsometry]]
*[[Endoscope]] inspection
*[[Guided wave testing]] (GWT)
*[[Hardness testing]]
*[[Impulse excitation technique]] (IET)
*[[Microwave imaging]]
*[[File:X-Ray, Optical and Terahertz image of a packaged IC.gif|alt=Nondestructive Testing of Packaged Items|thumb|609x609px|X-Ray, Optical and Terahertz image of a packaged IC.<ref>{{Cite journal|last=Ahi|first=Kiarash|date=2018|title=A Method and System for Enhancing the Resolution of Terahertz Imaging|url=https://www.researchgate.net/publication/326183918|journal=Measurement|volume=138|pages=614–619|doi=10.1016/j.measurement.2018.06.044|bibcode=2019Meas..138..614A |s2cid=116418505}}</ref>]][[Terahertz nondestructive evaluation]] (THz)
*[[Infrared and thermal testing]] (IR)
**[[Thermographic inspection]]
**[[Scanning thermal microscopy]]
*Laser testing
**[[Electronic speckle pattern interferometry]]
**[[Holographic interferometry]]
**[[Self-mixing laser interferometry]]
**[[Optical interferometry#Low-coherence interferometry|Low coherence interferometry]]
**[[Optical coherence tomography]] (OCT)
**[[Profilometer|Profilometry]]
**[[Shearography]]
*[[Leak#Leak testing|Leak testing]] (LT) or [[Leak detection]]
** [[Hydrostatic test]]
**[[Absolute pressure leak testing (pressure change)]]
**Bubble testing
**Halogen diode leak testing
**[[Hydrogen leak testing]]
**Mass spectrometer leak testing
**[[Tracer-gas leak testing method]] for helium, hydrogen and refrigerant gases
*[[Machine vision]] based automatic inspection 
*[[Magnetic resonance imaging]] (MRI) and [[NMR spectroscopy]]
* Metallographic replicas<ref>ASTM E1351: "Standard Practice for Production and Evaluation of Field Metallographic Replicas" (2006)</ref><ref>BS ISO 3057 "Non-destructive testing - Metallographic replica techniques of surface examination" (1998)</ref>
*Spectroscopy
**[[Near-infrared spectroscopy]] (NIRS)
** Mid-infrared spectroscopy (MIR)
** (Far-infrared =) [[Terahertz time-domain spectroscopy|Terahertz spectroscopy]]
** Raman Spectroscopy
*[[Optical microscope|Optical microscopy]]
*Positive material identification (PMI)
*[[Radiographic testing]] (RT) (see also [[Industrial radiography]] and [[Radiography]])
**[[Photostimulated luminescence|Computed radiography]]
**[[Digital radiography]] (real-time)
**[[Neutron imaging]]
**SCAR (small controlled area radiography)
**[[X-ray computed tomography]] (CT)
*Resonant inspection
**Resonant acoustic method (RAM)<ref>"Fundamentals of Resonant Acoustic Method NDT" (2005)</ref>
*[[Scanning electron microscope|Scanning electron microscopy]]
*[[Surface temper etch]] (Nital Etch)
*[[Ultrasonic testing]] (UT)
**[[Acoustic resonance technology]] (ART)
**Angle beam testing
**[[Electromagnetic acoustic transducer]] (EMAT) (non-contact)
**[[Laser ultrasonics]] (LUT)
**[[Internal rotary inspection system]] (IRIS) ultrasonics for tubes
**[[Phased array ultrasonics]] (PAUT)
**Thickness measurement
**[[Time of flight diffraction ultrasonics]] (TOFD)
**[[Time-of-flight ultrasonic determination of 3D elastic constants]] (TOF)
* Vibration analysis
*[[Visual inspection]] (VT)
**[[Pipeline video inspection]]
*[[Water weights|Weight and load testing]] of structures
* Corroscan/C-scan
* 3D computed tomography
**[[Industrial CT scanning]]
* Heat Exchanger Life Assessment System
* RTJ Flange Special Ultrasonic Testing