University of Wisconsin-Madison
Department of Engineering Physics, Engineering Mechanics Program
EMA 611, Advanced Mechanical Testing of Materials

Course Outline
Prerequisites: EMA 307 or equiv.; EMA 506; or consent of instructor;
Time and place: 2:25-3:40 MW, B321 Engineering Hall (EH). Labs and lectures will be in B321 EH, in 1313 EH or in 212 ERB as announced. Next planned offering is Spring 2009. Timetable 1 , Timetable 2
Instructor: Rod Lakes , Professor. Office-541 ERB. Office phone (608) 265-8697; fax: (608) 263-7451.

Left video: dynamic fringes in torsion. The fringes in the still images below center and right represent deformation of a bent bar. Both images were derived from the same transmission image-plane hologram. The hologram was made with red laser light and was illuminated with white light. The image on the left is of the hologram illuminated with conjugate white light. The image in the middle is of the hologram illuminated with oblique white light. The neutral axis of bending is revealed by the absence of color dispersion along the horizontal center line.


Outline
Goals: To prepare seniors and graduate students to do advanced design using engineering materials or do research in connection with mechanical properties of materials; development of physical insight.
Laboratory reports: Reports are due in class two weeks after the last laboratory session for a particular topic is held. Reports must be in paper form, not electronic. Report grades will be reduced by 10% for each working week (2% per day) of additional delay. Short homework assignments (hand written is OK unless otherwise stated) are due in class one week after they are assigned. The project report due date will be announced. Spring break and legal holidays are not counted in determining the due date. It is recommended that attention be directed toward the preparation of clear, understandable reports. For lab reports, share the data and write one report per person: do your own writing and graph plotting. For the final project report, the report writing may be a cooperative effort. Write all group member names on the face page of the report.
Grading: Grading is based on written laboratory reports, project report, and on homework and quizzes. The scale is 90-100% - A, etc.

Textbook: none
References:
[1] Saxby, G., Practical Holography, Prentice Hall, 1988.
[2] Schumann, W. and Dubas, M., Holographic Interferometry, Springer, 1979.
[3] Tufte, E., The Visual Display of Quantitative Information, Graphics Press, c1983.
[4] Dally, J., Experimental Stress Analysis, McGraw-Hill.
[5] Lakes, R., Viscoelastic Solids, CRC Press, 1998.

Experiments will be selected from the following. Please bring a 3.5" PC disk to each lab to capture data.
1--Transient studies with screw-driven machines
Tests of modulus and fracture strength. Rate dependence.

2--Ultrasonics and transducers
Piezoelectric transducers for ultrasonic measurements.
Transducers: calibration; time and frequency dependence.
Ultrasonic measurement of modulus.
Ultrasonic flaw detection

3--Servohydraulic testing machines
Principles of feedback control.
Load control, displacement control.
Rapid transients.
Oscillatory tests. Interpretation of phase angles.
Time dependence of materials in creep and relaxation.
Failure by yield, fracture, crushing; buckling of tubes.

4--Resonant ultrasound spectroscopy (RUS)
Mode structure of cubes and compact cylinders.
Determination of moduli.
Determination of mechanical damping.

5--Holographic interferometry and related methods
Interference of coherent light.
Full field deformation analysis.
Formation of holograms.
Principles of laser-viewable and white-light viewable holograms.
Fringe interpretation.
Moire fringes: formation and interpretation.

6--Optical methods in micromechanics
Point measurement of linear and angular displacement.
Study of vibration. Resonance structure.
Oscillatory tests. Interpretation of phase angles. Characterization of viscoelastic materials.

7-Project
A project will be conducted in the second part of the semester.

Successful class project. The holographic image at the upper segment contains time average fringes for torsional vibration of a bar. The central bright fringe represents the nodal line. Higher order fringes are of progressively lower contrast in accordance with theory. The bar is clamped at the upper left and is driven at the lower right.

Successful class project. The holographic image in the upper frame segment contains fringes for bending of a bar of dense polyethylene foam. The hologram is a reflection type illuminated with white light from a spotlight. The bar is clamped at the right and is loaded in the vertical direction (by a brass weight) at the left. In contrast to the bending fringes shown below, these fringes are vertical or nearly so. The reason is that the observation direction is different. A change in the camera angle reveals a change in the fringe pattern.

Successful class project. The holographic image in the upper frame segment contains fringes for bending of a plastic bar. The hologram is a reflection type illuminated with white light from a spotlight. The bar is clamped at the right and is loaded in the vertical direction (by a dead weight) at the left. Observe fringes on the clamp support (below). Therefore the support moved. Even though it is made of metal, there are interfaces which move. Observe also the discontinuity of fringe order at the horizontal boundary between the support and the bar. This signifies some slip has occurred during the bending. Observe the movement of the fringes. The camera angle was varied in the vertical direction, for each frame of the animation. Stop the animation if you want, by clicking on the image. The change in fringe order is due to motion orthogonal to the line of sight, in the direction of movement of the camera.

Successful class project. The holographic image in the upper frame segment contains laser transmission holographic fringes for indentation of a block of rubber by a small weight.

Successful class project. The holographic image in the upper frame segment shows bending fringes for wood. The weight is on the right. The knot of fringes on the right illustrates the free edge effect known in composite materials. The wood is heterogeneous, and that allows a concentration of deformation on the edge at the right, which is free of applied stress.