Extensometer for testing

[Jluc]

Hello everybody,

I am going to test elastomers in tension and compression in a large range of strain amplitude. These tests are at strain rate control and I would like to know if some people could give me references about extensometers that I can use to control the strain rates for large deformation in tension. I have the same question under compression?

Thanks for your help
Jean-Luc

[Jorgen]

In general, you can either use clip-on extensometers, or laser extensometers. For compression, people often simply calculate the strain from the crosshead displacement.

- Jorgen

[Jluc]

Hello Jörgen,

Thanks for your answer. In fact my problem is the following: When I check the different extensometers (clip on) available, there is some limitations for the admissible maximum of strain (100% in tension and maybe 30% in compression). It is fine for metals but not enough for elastomers. So how I can use a feedback loop in tension for a max strain of 300% or in compression for 100%. Are there extensometers or compressometers specific for polymers testing.

Thanks,

Jean-Luc

[Jorgen]

Yes, there are specific extensometers for elastomer-like materials. These extensometers can travel a long distance without reaching a maximum displacement.

- Jorgen