Down To the Bone
In medical research labs, universities and research hospitals, it is becoming increasingly common to perform studies on bone from human cadavers. Compression tests, bend tests and torsional tests on bone have become routine. That is not to say the tests are easy but they have become much more commonplace than they were years ago.
Maintaining the mechanical properties of bone requires special handling and storage. It is critical to keep the bone from drying out. Typically, specimens are kept in plastic bags and refrigerated to preserve them until it is time for testing.
The specimen must remain in refrigeration until just immediately before the start of the gage bonding process. Upon removal from refrigeration, select the strain gage location and use a razor blade or scalpel to remove any loose tissue from an area several times larger than the gage matrix. Scrub the gage location with a surgical gauze sponge with ether (if permissible) or Isopropyl Alcohol. Use of alcohol will require more extensive scrubbing. After scrubbing with the appropriate solvent, wipe the site dry using a single pass of a clean gauze sponge. This scrubbing removes remaining fatty material and locally dries the bone sufficiently to promote bonding.
Additional details on surface preparation are available in our Instruction Bulletin B-129-8 Surface Preparation for Gage Bonding: https://docs.micro-measurements.com/?id=2472
Immediately, bond the strain gage with M-Bond 200 adhesive per the instructions contained in the adhesive kit. https://www.micro-measurements.com/pca/detail/5e00e2cf9066dc1c0e3d292d
It is important to note that using small gages is preferred to keep the prepared area as small as possible. Micro-Measurements manufactures miniature linear, stacked and planar rosettes perfectly suited for these test requirements. These pre-cabled gages eliminate the need to solder lead wires to reduce the time between gage bonding and testing and prevents compromising the mechanical properties of the bone by localized heating.
G1350 pattern is a three element stacked rosette:
https://www.micro-measurements.com/pca/detail/5e937d8d9066dc4b1c041dcc
S5198 Pattern is a miniature, three element planar rosette:
https://docs.micro-measurements.com/?id=9790
S5145 pattern is a miniature linear pattern.
https://docs.micro-measurements.com/?id=12134
Micro-Measurements provides the necessary products to support such testing activity including strain gages, applications accessories and instrumentation. Additionally we have an extensive library of technical publications and training videos. Additionally, each year, our experts conduct numerous strain measurement workshops, all of which provide attendees with the necessary hands on skills to successfully a wide range of strain gage installations.
Visit our website https://www.micro-measurements.com/
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