Tension
Compression
Bending
Shear & Peel
Fatigue / High Rate
Torque
Combined Loading
Less than 0.1N
0.1 – 1 N
1 - 10 N
10 – 100 N
100 – 1000 N
1000 – 10,000 N
Strain Control
Liquid Baths
Custom Solutions

Tension

Summary

Specimens are typically clamped and pulled at a defined displacement rate while force/displacement data is captured. Force-controlled testing and cyclic testing are also common.

Unique to Biomaterials

Specimens must be fixed to the system without causing weakness at the attachment site. Biomaterials are often soft, slippery, or have irregular shapes and hence require specialized fixtures to achieve good results.
Most biomaterials testing applications require image-based measurement techniques to directly measure specimen geometries and strain values.

Common Applications:

  • Muscle, skin, and tendon tissues
  • Blood vessels
  • Plant structures

Compression Testing

Summary

Parallel plate compression involves crushing a specimen that typically has flat, parallel upper and lower surfaces and a constant cross section. Variations include indentation (spherical or other geometries), puncture, burst testing.

Unique to Biomaterials

Time-correlated images are helpful to understand test results, especially if the specimen geometries are irregular or material properties are non-homogeneous.  

Very small fixtures and low force sensors are commonly used with the UniVert to test small delicate materials. The MicroTester can be used for even smaller specimens and can achieve force resolutions of 10nN.

Common Applications

  • Hydrogels
  • Bone
  • Cartilage

Bending

Summary

Specimens are typically long and thin and are supported at each end by fixed supports. Load is applied at 1 or 2 points between the fixed supports. This is often a test to failure.

Unique to Biomaterials

The irregular shapes and variability in biological structures require appropriate fixtures, protocols, and expertise to ensure reliable data. Time-correlated images are helpful to understand test results, especially if the specimen geometries are irregular or material properties are non-homogeneous.  

For very delicate specimens such as plant fibers or mouse tissues, the MicroTester can be used and can achieve force resolutions of 10nN.

Common Applications

  • Rodent long bones
  • Orthopaedic devices
  • Plant structures

Shear & Peel

Summary

Peel testing is used to characterize the strength of the adhesion of one material to another with a normal load. Shear testing to characterize a materials response to shear loads or the adhesion strength of one material to another with a shear load.

Unique to Biomaterials

Biomaterials are often soft, slippery, or have irregular shapes and hence require specialized fixtures to achieve good results.

Adhesion is often affected by temperature and humidity. The UniVert can be efficiently equipped with the necessary environmental control accessories. 

Common Applications

  • Tapes, glues, and sealants
  • Rubbers, gels, and other soft 3-dimensional materials

Fatigue / High Rate

Summary

Fatigue testing involves loading a specimen over many cycles to determine the impact on its mechanical response. The loading can be tensile, compressive, bending, inflation, or any other mode. High rate testing involves loading the specimen at high strain rates to determine how the response of the material varies with strain rate. 

Both fatigue and high strain rate testing benefit from an actuator that is capable of high accelerations and velocities. The UniVert system can be fitted with an auxiliary actuator to efficiently meet these requirements.

Unique to Biomaterials

This type of testing is often in musculo-skeletal and cardiovascular tissues that would normally be subjected to cyclic loading in vivo. For basic research, the testing can be easily configured to replicate in vivo conditions. For some orthopaedic materials and applications, established test standards exist.

Common Applications

  • Musculo-skeletal tissues and synthetic alternatives
  • Cardiovascular tissues such as arteries and hear valves

Torque

Summary

Specimens are typically supported at each end by platens (with compressive load), grips, or jaws similar to a drill chuck. Any protocol specified in terms of axial displacement, axial force, torque, or rotation can be specified.

Unique to Biomaterials

This type of testing is often used to evaluate bones, joints, or similar synthetic materials. The UniVert system can be easily configured to match protocols used in previous research.

Common Applications

  • Rodent long bones and/or joints
  • Arteries
  • Composite materials

Combined Loading

Summary

The UniVert is always equipped with uniaxial linear capabilities. In addition, it can support up to 2 more additional loading mechanisms and all of the subsystems can be used simultaneously in a single test protocol. Common configurations include:

  • torque-tension (e.g. arteries)
  • torque-compression (e.g. joints)
  • tension-pressure (e.g. arteries)
  • compression-shear (muscle)

Less than 0.1N Force Range

Summary

The UniVert systems can be used for testing between 0.1N and 10kN. For testing below 0.1N, the use of the MicroTester system is recommended.

 

0.1 – 1 N

Summary

The UniVert can be equipped with patent pending low force load sensors. These sensors provide unparalleled force sensitivity and overload protection. They are compatible with custom fixtures for tension, compression, indentation, and other test types.

Due to patent activity, further details will be posted in January 2025.s

 

1 – 10 N

Summary

The UniVert can be equipped with patent pending low force load sensors. These sensors provide unparalleled force sensitivity and overload protection. They are compatible with custom fixtures for tension, compression, indentation, and other test types.

Due to patent activity, further details will be posted in January 2025.

 

10 – 100 N

Summary

In this force range, the UniVert is typically equipped with a miniature S-beam load cell and plastic fixtures to minimize the offset force. These sensors and fixtures can be fitted to the UniVert S, 1kN, and 10kN models.

Common Applications

  • Small animal tissues
  • Hydrogels
  • Rubbers and other compliant materials

 

100 – 1000 N

Summary

In this force range, the UniVert is typically equipped with an S-beam load cell and stainless steel fixtures to suitably support the test specimens. These sensors and fixtures can be fitted to the UniVert S (max 200N), 1kN, and 10kN models.

Common Applications

  • Small specimens of all types
  • Educational labs (particularly UniVert S model)

1000 – 10,000 N

Summary

In this force range, the UniVert is typically equipped with an S-beam load cell and stainless steel fixtures to suitably support the test specimens. These sensors and fixtures can be fitted to the UniVert 10kN models.

Common Applications

  • Specimens of all types
  • Departmental facilities

 

Strain Control

Summary

For any given test, the specimen may not deform as expected due to grip slipping, non-uniform material properties, or misalignment. When equipped with a suitable imaging system, the UniVert software can measure the specimen strain is real time by tracking features on the specimen surface. This information can be used to modulate the cross head motion to achieve the strain profile prescribed in the test method. This ensures that results of multiple tests can be easily compared and that combined loading protocols are well synchronized. 

Unique to Biomaterials

Biomaterials are often more complex than other engineered materials. The use of non-contact strain measurement tools to achieve true strain control is a powerful tool.

Liquid Baths

Summary

Temperature-controlled liquid baths are used to maintain consistent hydration and temperature conditions when working with materials

Unique to Biomaterials

This type of testing is often in musculo-skeletal and cardiovascular tissues that would normally be subjected to cyclic loading in vivo. For basic research, the system can be easily customized to replicate in vivo conditions. For some orthopaedic materials and applications, established test standards exist.

Common Applications

  • Musculo-skeletal tissues and synthetic alternatives
  • Cardiovascular tissues such as arteries and hear valves

Custom Solutions

Summary

Due to the wide variety of applications within the biomaterials space, the UniVert has been carefully designed with a broad range of configurations. Even so, there is often a need to custom fixtures, controls, environmental accommodations, or other functionality. CellScale has a long history of successfully and efficiently collaborating with our customers to achieve successful research outcomes. 

If you have a difficult application, we would be happy to engage with you and support your research with a custom solution.