What Is Rheology?
Rheology or Rheometry is the scientific study of how materials deform and flow under applied forces. It captures the interplay of viscosity (resistance to flow), elasticity (reversible deformation), and viscoelasticity (time-dependent behavior) in materials.
Viscosity, one of the core parameters in rheology, is important for characterizing a material’s resistance to flow, which directly impacts processing methods such as pumping, mixing, spraying, and spreading in applications ranging from pharmaceuticals to coatings and food products. At Covalent Metrology, we have an Anton Paar MCR 302 rotational rheometer equipped with a peltier stage.
Broad Material Compatibility
Broad Material Compatibility
Handles liquids, gels, pastes, and soft solids with versatile measurement modes.
Precise Environmental Control
Precise Environmental Control
Offers –20°C to 200°C testing with evaporation blocker for volatile samples.
Advanced Testing Flexibility
Advanced Testing Flexibility
Supports rotational, oscillatory, creep, stress relaxation, UV curing, and tribology studies.
Why Use Rheology Testing?
Rheological testing is valued for its versatility and precision in characterizing material behavior. Rheology enables quantitative analysis of flow and deformation under real-world conditions.
Industries Served:
- Pharmaceuticals.
- Food and Beverage.
- Batteries and Energy Storage.
- Plastics and Polymers.
- Adhesives and Sealants.
- Biomedical and Cosmetics.
- Oil and Gas.
- Paints, Coatings, and Inks.
- Environmental Science.
Quantitative Flow and Deformation Analysis
Measures viscosity, elasticity, and viscoelasticity to simulate real-world material behavior.
Cross-Industry Applications
Widely used in pharmaceuticals, food, polymers, batteries, coatings, and biomedical fields.
Supports Product Development and QA
Provides data to optimize processing, stability, and performance of complex materials.
Working Principle
In a rheological test, the sample is placed between two geometries (e.g., cone-plate, parallel plate, or cup-and-bob), and a controlled shear stress or strain is applied. The instrument measures the resulting torque, displacement, and normal force to determine properties like viscosity, complex modulus, and damping behavior. This process helps simulate real-world conditions such as spreading, mixing, or flowing through a pipe.
Equipment Used for Rheology:
Anton Paar MCR 302
- Features:
- Rotational rheometer with Peltier temperature control.
- Geometries Supported: Cone-plate, parallel plate, cup-and-bob.
- Optional setups: Tribology cell, UV cure.
- Air-bearing-supported EC motor.
- Available with flow, rotational, and oscillatory mode.
- Torque Range (Rotation): 0.5 nNm to 200 mNm.
- Torque Range (Oscillation): 7.5 nNm to 200 mNm.
- Variable Temperature Range: 20°C to 200°C.
Key Differentiators
In a rheometry test, a sample is subject to shearing with preset speed, frequency and temperature conditions –which can be either static or dynamic.
Strengths
- Broad applicability across liquids, gels, and soft solids.
- Precise temperature control from –20°C to 200°C.
Limitations
- Limited automation and throughput.
- High operator dependency for complex samples.
- Requires sufficient sample volume for reliable results.
Unsure whether Rheology is Right for You?
Learn more about using Rheology testing services today.
Sample Information
Frequency sweep of silicone oil showing viscoelastic crossover point between storage modulus (G′) and loss modulus (G″).
What we accept:
- Liquid/Fluid Samples: Typically, several mL preferred.
- Solid Samples: 25 mm or 50 mm diameter discs.
- Semisolid (gel, paste, ointment) or fluid phase (solution, slurry, liquid).
- Semisolid stiffness upper limit: up to a few decades of kPa.
- Fluid material viscosity lower limit: down to 1 mPa·s (1 cps).
Use Cases
Pharmaceuticals
Viscoelastic property analysis of gels and soft solids.
Food & Beverages
Thixotropy characterization.
Batteries & Energy Storage
DMA testing of polymer films and composites.
Plastics & Polymers
Curing studies of thermosets (e.g., epoxy resins).
Biomedical & Cosmetics
Tribological assessments.
Oil & Gas
Viscosity profiling of oils, greases, and emulsions.
Paints / Coatings / Ink
Determination of gel point.
Environmental Science
Flow curve development for slurries and dispersions.
Complementary Techniques
- DSC (Differential Scanning Calorimetry): For thermal transitions like Tg or melting; curing studies.
- FTIR (Fourier Transform Infrared Spectroscopy) and GC-MS (Gas Chromatography-Mass Spectrometry): To identify volatile. components.
- TGA (Thermogravimetric Analysis): For mass loss behavior.
Differential Scanning Calorimetry (DSC)
Quantifies heat flow for material optimization. Explore
Fourier Transform Infrared Spectroscopy (FTIR)
Rapid, non-destructive molecular fingerprinting across materials. Explore
Gas Chromatography-Mass Spectrometry (GC-MS)
Identifies and quantifies small organic molecules in mixtures. Explore
Thermogravimetric Analysis (TGA)
Measures material mass changes with temperature or time. Explore
Why Choose Covalent for Your Rheology Needs?
Frequently Asked Questions
Identifying the right text can be complex, but it doesn’t have to be complicated.
Here are some questions we are frequently asked.
What types of samples can Covalent test with rheology?
We test liquids, gels, soft solids, and polymers, including pharmaceutical creams, electrode slurries, adhesives, and food emulsions.
Can you perform oscillatory and steady shear tests?
Yes, we can perform both oscillatory and steady shear tests.
What are your temperature capabilities?
We can test from –20°C to 200°C (Peltier).
How fast can I get results?
Turnaround time is typically 5 business days.
