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1 1 Scarsdale Road, Don Mills, ON, M3B 2R2 Tel: , Fax: Montreal: , Ottawa: , Winnipeg: , Calgary: , Vancouver: Website:

2 Reflection Polariscopes For PhotoStress analysis, two instrumentation systems are available. The 030 Series Modular Polariscope System has been the reflection polariscope standard in both industrial and educational laboratories for the past 25 years. Its modular design permits a broad range of strain measurement capabilities. For example, the polariscope can be equipped with a null-balance compensator as well as a digital strain indicator/printer. And, measurements made on small parts or in regions of high stress concentration are both easier and more accurate when the optional telemicroscope accessory is attached. The Model 040 is an innovative reflection polariscope incorporating numerous built-in features. These include an integral null-balance compensator and associated electronics for direct display of measurements of both stress and strain. Compact and portable, this instrument can be operated either from an ac power line or 12-Vdc automobile battery. Model 040 Polariscope with on-board electronics. 030 Series Polariscope equipped with Model 632 System for electronic display and recording of strain data

3 Accessories Camera Accessory and Model 335 Camera shown mounted to Model 040 Polariscope for photographic recording of PhotoStress patterns. PhotoStress patterns can also be recorded with video, high-speed, or digital photographic recording devices. The PhotoStress Separator Gauge and Model 330 Interface Module, when used in conjunction with the 030 Series and Model 040 Polariscopes, permits fast and accurate determination of the separate principal strain values at any point on the coated part. This unique gauge is produced by the Micro-Measurements Division of Vishay Measurements Group, Inc. Model 137 Telemicroscope for providing magnified view of test points in regions of high stress gradient. PhotoStress Coatings are available in a wide variety for application to test parts and structures made from almost any type of material. Specially designed Application Kits simplify the process of preparing an applying the PhotoStress plastic to the surface of the test part.

4 Fringe Number: ±4.00, resolution Fringe Constant Setting: 500 to 10,000 µε/fringe, resolution 10µε. Strain Reading: 0 to 20,000µε (X1 range), resolution 10µε. 0 to 40,000µε (X10 range), resolution 100µε. Stress Reading: For High-Modulus Material Settings: ±199.9 x 10 3 psi (X1 range), resolution 100 psi; ±1999 x 10 3 psi (X10 range), resolution 1000 psi; For Low-Modulus Material Settings: ±1.999 x 10 3 psi (X1 range), resolution 1 psi. ±19.99 x 10 3 psi (X10 range), resolution 10 psi. Sensitivity: Principal strain angles, ±1. Strain magnitudes, ±0.01 fringe [approximately 50 psi (350 kpa) on aluminum, 150 psi (1050 kpa) on steel, when used with type PS-1A coating]. Light Source: 100W lamp, fan-cooled. 12V transformer included. Power: 115/230 Vac, 50/60 Hz. Polarizing and Quarter-Wave Filters: Glass-laminated and ball-bearing mounted, with assemblies mechanically coupled for synchronous rotation. Specifications 040 Polariscope Angle: 0 to 90 deg, resolution 1 deg. Electronic Accuracy: ±1% of reading, ±1 active count (typical). LED Digital Display: Angle: Two digits. Magnitude: 3-1/2 digits active with polarity and fixed-zero digit. Analog Output: Angle: 10 mv/count (+900 mv full scale). Magnitude: 1 mv/count (±1.999V full scale). Light Source: 100 W lamp, fan-cooled Power Requirements: 115/230 Vac, 50/60 Hz; 12 Vdc optional. Size & Weight (Basic Unit): 13.1 H x 6.6 W x 6 D in (333 x 168 x 153 mm), 5 lb (2.3 kg). 030 Polariscope Accessories for Model 030 Model 632 Digital Indicator Magnitude Range: 0 to 19,990µε (X1 range); 0 to 50,000µε (X10 range). Angular Measurement Range: 0 to 90.0 deg. Magnitude Accuracy: 10µε or 1% of reading, whichever is greater. Angle Accuracy: 1 deg. Fringe Constant Selection Range: 0 to 9999 µε/fringe. Compensator Linearity: ±0.005 fringe. Print Format: Measurement Point: 00 to 99. Polarity: + for positive; - for negative. Magnitude: 0 to 19,990µε (X1 range); 0 to 50,000µε (X10 range). Angle: 0 to ±90.0 deg. in 1-deg. increments. Overrange: Prints asterisk (*) in overrange columns. Columns: 10 active. Tape: 2-1/4 in. W X 150 yd L (57 mm x m) roll, black-on-white thermal print paper. Power: 115/230 Vac ±10%, 50/60 Hz, 20W typical. Measurement Point Display: 00 to 99 LED with automatic and manual advance and reset to zero. Analog Outputs for Computer Usage: 100 µv/µε to 1.1 mv/µε at fringe constant of (nominal). 10 mv/deg. to 110 mv/deg. (nominal, limited to ±2.50 Vdc). Model 335 Camera This high-quality single-lens reflex camera offers through-the-lens viewing for easy, rapid positioning and accurate focusing. Permanent recording of PhotoStress patterns for later study or presentation in test reports is described in detail in Tech Note TN-702. Model 036 Monochromator Camera Accessory A high-quality interferential optical filter with a narrow bandpass corresponding to the exact wavelength where fringes are observed in white light. These are two principal applications of monochromatic light in PhotoStress testing: (1) black and white photography, and (2) presentation of fringe density and contrast irrespective of the number of fringes occurring in the PhotoStress pattern. The Model 036 Monochromator is mounted in a special threaded housing for attachment to the camera lens. Accessories for Model 030/040 Basic Reflection Polariscope Includes: Optical head assembly. High-intensity light source. Fitted carrying case. Heavy-duty elevating tripod, with three-way adjustable head and carrying case. Detachable handgrip for portable operation. Spare lamp for light source. Comprehensive instruction manual. Camera bracket. Weigh (Basic Unit): 4.4 lb (2 Kg). Model 232 Uniform-Field Compensator As an alternate to the Model 632, a compact, manual compensator can be used for measuring the photoelastic fringe value. The measured fringe value can then be converted to strain by applying the fringe-constant of the PhotoStress coating. The optical specifications of the Model 232 Manual Compensator are identical to those of the Model 632 s Compensator, with resolution of 0.01 fringe, and nominal range of 4-1/2 fringes. Model 232-RE Compensator Range Extender For measurements at high strain levels requiring more than 4-1/2 fringes of compensation, the range of the Model 632 or 232 Compensator can be extended to 9 fringes (nominal) my installing the clip-on Model 232-RE Range Extender. Model 033 Oblique-Incidence Adapter Model 137 Telemicroscope The telemicroscope greatly expands the capabilities of the 030 Series PhotoStress System, providing a magnified view of the measurement area for detailed analysis in regions of high strain gradient (stress concentration), and for measurements at extended working distances. It also provides for close-up examination, with magnification up to 15X, when measuring stress concentration in regions of high strain gradient. PhotoStress Separator Gauge A unique electrical resistance gauge that measures the sum of the principal strains. This data, when coupled with the measured difference of principal strains made with the 030 Series or Model 040 Reflection Polariscope, provides the separate principal strain values. The PhotoStress Separator Gauge has special design features for ease of use and optimum performance in PhotoStress applications, including pre-attached leadwires and polyimide encapsulation. Gauges are supplied three-to-a-package. Model 330 Interface Module A four-channel switch-and-balance unit with precision resistive circuits for reducing gauge excitation voltage to minimize self-heating effects for use with the Vishay Measurements Group P-3500 Strain Indicator.

5 What is PhotoStress? PhotoStress is a full-field technique used in stress analysis testing. Initial observation of a photoelastic pattern provides quick qualitative analysis of the overall stress distribution, and then accurate quantitative data at any selected point(s) is easily obtained using straightforward measurement techniques and modern optical instrumentation. When a photoelastic material is subjected to load and viewed with polarized light, the colorful patterns seen are directly proportional to the stresses and strains in the material. The photoelastic color sequence observed with increasing stress is: black (zero), then yellow, red, bluegreen, yellow, red, green, etc. The transition line between the red and green colors is defined as a fringe (from the phenomenon of birefringence). As the stress increases, the number of fringes increases proportionally. (See adjacent photo.) When the stress gradient becomes steeper, these color bands, or fringes, are closely spaced. Conversely, the appearance of a uniform color represents a uniformly stressed area. In brief, the overall stress distribution can easily be studied by recognizing fringes, their numerical order, and spacing with respect to one another. With PhotoStress, a specially formulated plastic coating is bonded to the actual test part or structure. Then, as Force Direction test or service loads are applied, the coating is illuminated with polarized light from the measurement instrumentation, in this case called a reflection polariscope. Quantitative analysis of both the strain direction and magnitude at any point on the coated surface is easily performed with the reflection polariscope and its companion digital strain indicator. Primary Advantages Provides an accurate, economical, and portable means for stress analysis of virtually any part or structure, regardless of geometric complexity or material composition. Example shown - investigation of stresses on aircraft structure support member. Can be used in laboratory or in the field, and is unaffected by humidity or time. Gives direct strain measurements on real parts/structures under static or dynamic loads. No modeling is required. Observation and measurement of assembly stresses as mating components are joined. Detection of yielding, since any deformation of the test material is displayed in the coating after the load is removed. Identification of residual stresses.