UltraSonicators for ASTM D2603 Shear Stability Testing
The ASTM D2603 standard describes the sonic shear stability testing of hydraulic fluids under ultra-sonically induced shear stress. Hielscher ultra-sonicators are used as reliable shear creating devices used for shear stability testing of hydraulic fluids in accordance to ASTM D2603 Standard Test Method for Sonic Shear Stability of Polymer-Containing Oils.
ASTM D2603 – Ultra-Sonic Shear Stability of Polymer-Containing Oils
Purpose: Hydraulic fluids, engine oils, transmission fluids for cars, tractor fluids and other power transmission fluids are exposed to shear forces of varying degrees during usual operation, which can lead to changes in viscosity and a subsequent decrease in efficiency. In order to improve the viscosity index of hydraulic fluids, polymers are added to these fluids. The ASTM D2603 test examines viscosity changes in polymer-containing fluids exposed to ultrasound-induced shear forces, so-called sonic shearing vibrations.
Application: It is goal of the ASTM D2603 protocol to determine the viscosity of the sample. Therefore, the sample is placed in the test beaker, tempered to the specified testing temperature and sonicated using an ultra-sonic probe for the time specified in the test protocol ASTM D2603. Subsequently, the resulting viscosity of the fluid is measured and the exact change in viscosity is reported in percentage.
Hydraulic fluids
Petro Industry
Material Science
Quality Control
Research & Development
The test method specified in the ASTM D2603 protocol permits the evaluation of shear stability with minimum interference from thermal and oxidative factors that may be present in some applications. It has been found applicable to hydraulic fluids containing both readily sheared and shear-resistant polymers. The correlation with performance in the case of hydraulic applications has been established.

Ultra-Sonic Shear System UP400St (24kHz, 400W) for ASTM D2603 Sonic Shear Stability Testing
What Do I Need for ASTM D2603 Ultra-Sonic Shear Stability Testing?
- UltraSonicator: a probe-type ultra-sonic device with a fixed frequency oscillator and ultra-sonic horn (also known as probe or sonotrode). A typical ultrasonic device used for ASTM D2603 testing is the UP400ST (24kHz, 400W) with ultrasonic probe (horn / sonotrode) S24d22.
- Water / ice bath: Cooling water bath or ice bath in order to maintain a desired temperature such as 0°C.
- Temperature sensor such as PT100 (included with the ultrasonic devices UP400ST)
- Griffin 50mL beaker, made from borosilicate glass.
- Sound enclosure (optional): A sound protection box to enclose the ultra-sonic horn to reduce the noise level produced by the sonic shear device.
- Viscometer: any viscometer and bath that meet the requirements of Test Method D445 are sufficient.
- Reference fluids: The primary reference fluid is ASTM Reference Fluid A, a petroleum oil containing a polymer capable of being broken down by turbulence at high rates of shear. This oil has the following typical properties: This oil has a viscosity of about 10.8 mm2/s (cSt) at 100°C and a viscosity of about 58 mm2/s (cSt) at 40°C.
A second reference fluid is ASTM Reference Fluid B, a petroleum oil containing a polymer capable of being broken down by turbulence at high rates of shear. This oil has a viscosity of about 13.6 mm2/s (cSt) at 40°C.
Why Hielscher Ultra-Sonicators for ASTM D2603 Testings?
Hielscher Ultrasonics supplies high-performance ultrasonic shear devices for shear stability tests according to ASTM D2603 and ASTM D5621. With a fixed frequency, reliable ultrasonic shear power, Hielscher ultra-sonic shear devices are ideal for shear stability evaluation of hydraulic fluids. Hielscher ultrasonicators are equipped with smart software and settings, which allow for sophisticated testings according to ASTM standards. The menu is easily accessible via digital touch display or browser remote control. While the frequency is fixed, which is important for reliable sonication results and ASTM standards, the amplitude can be precisely set to a desired stroke impact.
Calibration of Hielscher ultrasonicators is simple and and can be rapidly and easy done via the sophisticated menu. All digital ultrasonicators are equipped with pluggable temperature sensor, which continuously records the sample temperature and transmits it back to the ultrasonic generator, where all important sonication data such as amplitude, sonication time and duration, temperature, and pressure (when pressure sensor is mounted) are recorded automatically on a built-in SD-card. These smart features allow for reliable and reproducible ultra-sonic shear tests and make the operation user-friendly and safe.
Hielscher Ultrasonics devices for shear stability tests are conform with both, ASTM D-2603 and D-5621 standards.
- fixed amplitude
- smart software with timer for exact sonication duration
- digital, coloured touch-screen
- smart settings
- intuitive menu
- automatic data recording on SD-card
- integrated temperature sensor
- sample illumination
- precise control
- easy to calibrate
- reproducible results
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Various types of sonotrodes (probes / horns) for the sonic shear device UP400ST, which can be used for ASTM D2603 – Standard Test Method for Sonic Shear Stability of Polymer-Containing Oils
Literature / References
- ASTM D2603-20, Standard Test Method for Sonic Shear Stability of Polymer-Containing Oils, ASTM International, West Conshohocken, PA, 2020.
- ASTM D5621-20, Standard Test Method for Sonic Shear Stability of Hydraulic Fluids, ASTM International, West Conshohocken, PA, 2020.
Scope of the ASTM D2603 Ultra-Sonic Shear Stability Test Protocol
- This test method covers the evaluation of the shear stability of hydraulic fluids in terms of the final viscosity that results from irradiating a sample of the hydraulic fluid in a sonic oscillator.
- Evidence has been presented that a good correlation exists between the shear degradation that results from sonic oscillation and that obtained in a vane pump test procedure.
This test method uses millimetres squared per second (mm2/s), an SI unit, as the unit of viscosity. For information, the equivalent unit, cSt, is shown in parentheses. - This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
- This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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