Non-destructive Tests

Non-destructive Tests

Research and applicative activities on non-destructive testing and structural health monitoring of structural materials and components are performed both experimentally and numerically. Traditional and advanced techniques are employed, while innovative ones are developed. Additionally, in-service monitoring and prognostics are studied and implemented.

INSTRUMENTS & FACILITIES

  • Harfang X32 phased array ultrasonic flaw detector with 2.25, 5 and 10 MHz probes. Encoders for C-Scan mapping
  • Eddify M2M Mantis phased array ultrasonic flaw detector with 2.25 and 5 MHz probes. TOFD, conventional ultrasonic channels and TFM functionalities are available, as well
  • RDG500 and RDG2500 conventional ultrasonic flaw detectors with straight, twin, angled and creeping probes
  • Innerspec Temate Powerbox H EMAT ultrasonic flaw detector with permanent magnets and coils for different beam forming opportunities
  • Specific equipment for implementing and managing Lamb and guided ultrasonic waves
  • Vallen AMSY-6 acoustic emission unit (8-channels). Managed by the PoliNDT interdepartmental lab
  • Nortec 1000S+ eddy current flaw detector with probes working at a 500-2000 Hz frequency range
  • NSI X25 x-ray micro-computed tomography scanner. Managed by the AMALA interdepartmental lab
  • Electromagnetic yokes and permanent magnets for colour contrast and fluorescent magnetic particles (calibration blocks, luxmeter, radiometer, UV lights, ASME probe, gaussmeter)
  • Colour contrast and fluorescent liquid penetrants (calibration blocks, luxmeter, radiometer, UV lights, thermocouples, chronometer)
  • Lenses, mirrors and dedicated white and black lights for visual testing
  • CIVAnde specific software package for NDT simulations (ultrasonic testing, eddy current testing, radiographic testing and x-ray computed tomography)
  • AST X-Stress 3000 portable X-ray diffractometer
  • Equipment for holographic interferometry and for transmission and reflection photo-elasticity.

ACTIVITIES

Experimental and numerical characterization of NDT capabilities

  • Characterization of experimental “Probability of Detection” curves for different NDT methods
  • Characterization of numerical “Model Assisted Probability of Detection” and “Multi-Parameter Probability of Detection” curves for different NDT methods
  • Interaction between NDT capabilities and the damage tolerant design approach

Traditional and advanced ultrasonic testing of materials and components

  • Phased array monitoring of fatigue crack propagation in adhesive bonded composite lap-joints
  • TOFD inspection of welded and seamless metallic pipes
  • Guided waves monitoring of pipes and rails
  • Residual stress measurements in railway wheels by EMAT
  • Application of creeping waves to coarse grain metals

Structural health monitoring by ultrasonic lamb waves

  • Determination and characterization of dispersion curves in metallic, composite and polymeric components
  • Definition of an innovative way to induce a single anti-symmetric propagation mode of Lamb waves
  • Analysis of the reflection and transmission of Lamb waves through artificial delaminations in composite laminates
  • Analysis of the reflection and transmission of Lamb waves through natural defects, obtained by low energy impacts, in composite laminates

Structural health monitoring by acoustic emission

  • In-service monitoring of railway axles by means of acoustic emission
  • In-service monitoring of adhesive bonded joints by means of acoustic emission
  • Comparison of acoustic emission response with optical, micro-computed tomography scans and ultrasonic NDT approaches during crack propagation tests
  • Comparison of acoustic emission response with low frequency vibrations during crack propagation tests
  • Post-processing and interpretation of acoustic emission data by machine learning and artificial intelligence

Eddy current testing of corrosion-fatigue phenomena

  • Experimental eddy current measurements of developing corrosion-fatigue damage in small-scale specimens and full-scale components
  • Correlation between damage and eddy current response at different stages of corrosion-fatigue life
  • Numerical simulations of eddy current response at different stages of corrosion-fatigue life