(Don’t) Send in the Reinforcements
When testing materials with very low modulus of elasticity or when manufacturing very low capacity load cells or other transducers, the localized reinforcement created by the strain gage sensor installation will have a potentially dramatic influence on the measurement accuracy.
The installation of strain gage sensors, adhesives and protective coatings will locally reinforce, and therefore change the behavior of, the material to which they are bonded. This is a serious problem for the stress analysist and transducer design engineer alike.
To minimize this problem, open face strain gage sensors and thin layers of low modulus coatings should be used whenever possible when testing materials like human or animal tissue as well as in very low capacity transducers. In transducer applications, the application of protective coatings will not only reduce sensitivity but also change creep performance and linearity. Also, especially on thin materials, keep solder connections at the strain gage tabs as small as possible.
When faced with these types of applications, consult with Micro-Measurements experts at email@example.com.