AAE 55200: Nondestructive Evaluation of Structures and Materials

Description

Overview of methods employed for nondestructive evaluation of structures and materials taught in the context of damage tolerant structural analysis. Major inspection topics include: radiography, ultrasonics, eddy current, penetrant, magnetic, and visual/optical techniques. Other new emerging inspection techniques also are discussed.

Format 3 hrs lecture per week
Credit hours 3
Status Elective, Structures
Offered Spring
Pre-requisite AAE 204 or CE 273 or equivalent (offered in alternate years)
Co-requisite None
Course Instructor Professor Grandt
Text R. Halmshaw, Non-Destructive Testing, Edward Arnold, 1991. Class notes are also distributed.
Assessment Method

Midterm examination (30%); comprehensive final examination (35%); term paper 1 – a written literature review of a new research topic in NDE (15%); term paper 2 – a written and oral presentation dealing with application of an NDE method to a practical engineering situation (20%)

Course Objective:

Overview the concepts, principles, and methods employed for nondestructive evaluation (NDE) of structures and materials. While emphasis is on inspection methods employed to ensure structural integrity of aerospace vehicles, course content has application to a broad class of high performance structures. Major NDE techniques covered include X-rays, ultrasonics, eddy currents, penetrants, magnetic flux, and visual/optical methods. Further topics such as damage-tolerant design, retirement-for-cause, factors affecting NDE reliability, and structural "aging" are discussed in the context of NDE engineering

Necessary Background:

  1. Vector calculus and differential equations through PDE's
  2. Basic understanding of strength of materials (i.e. concepts of stress and strain, mechanical properties of materials)

Topics (number of Lectures):

  1. Introduction (5 classes) class mechanics, types of damage, failure criteria, LEFM summary, overview of major NDE techniques
  2. Probability of Detection (2 classes)
  3. Visual Inspection (2 classes) visual aids, borescopes, case histories
  4. Radiography (6 classes) overview, absorption/scatter mechanisms, x-ray and gamma-ray sources, image formation (film, screens, arrays), image quality (scatter control, screens), image formation (geometric factors, uncertainty, IQI's), neutron radiography, computed tomography, safety
  5. Ultrasonics (6 classes) overview, sound waves, boundary interactions (impedance, reflection/refraction, critical angles, corners), attenuation, ultrasonic techniques, sources of ultrasound (piezoelastic materials, EMAT, laser), scans, parameter selection
  6. Eddy Current (5 classes), overview, coil types, coil arrangements, operating variables, impedance (impedance versus conductance, lift-off, and thickness), frequency effects
  7. Magnetic Particle (4 classes) overview magnetic principles, methods for generating magnetic fields, magnetic hysteresis/demagnetization, magnetic flux sensors (visual and nonvisual), other magnetic methods
  8. Dye Penetrant (1 class) overview, classification procedures (type, removal method), developers, safety
  9. Acoustic Emission (2 classes) overview, AE Signals/sensors, AE techniques
  10. Advanced Optical (2 classes) interferometry, holography, Moire, diffracto-sight
  11. Special Topics (4 classes) guest speakers, laboratory demonstrations
  12. Activities (6 classes) midterm exam, term paper presentations, final exam

Relationship of course to program objectives:

This elective course develops technical expertise in nondestructive methods for evaluating the structural integrity of structures and materials. Knowledge of inspection methods is an important technical component of aerospace engineering and design (program Objective 1). The role of inspection in preserving structural integrity and protecting public safety is discussed through several case histories (Objective 4). Students are required to research and prepare one term paper on a new inspection method and another paper on applications of inspection techniques to solve practical engineering problems (Objective 3). Both major papers are presented in written form, and one is also given orally in class (Objective 2c).

Prepared by: A. F. Grandt, Jr.

Date: February 14, 2001