Thermal and rheological testing laboratory with weathering

HDT and Vicat test system CEAST HV500 Instron

Close-up image of a Instron CEAST specimen, Source: IfBB

The heat distortion resistance is the ability of a test piece to maintain its shape up to a certain temperature and under a certain load condition or at a predetermined test temperature without exceeding a predetermined deformation amount. The most important test methods for heat distortion resistance are Heat-Distortion-Temperature [°C], HDT according to DIN EN ISO 75-1 to 75-3 and Vicat-softening temperature [°C] VICAT Softening Temperature, VST according to DIN EN ISO 306.

Technical details:

Temperature range: up to 500 °C
Temperature ramps: 50 °C/h and 120 °C/h
Heat transfer medium: alumina powder
Heating bath capacity: 11.5 liters
LVDT sensors: 3 (per station)
Thermocouples: 3 (per station)
Bath temperature sensor: 1
Automatic calculation and display of necessary load weights
Temperature-dependent, automatic compensation of the thermal expansion of the test station in each experiment
Electrical connection: 230 V, 50 Hz
Compressed air connection: 5 bar
Power: 4500 W

Measuring principle:
The specimen is subjected to a three-point bend under constant load to produce a bending stress. The temperature in the heat transfer medium is increased at a uniform rate. The temperature value is measured at a defined standard deflection.

Dynamic-mechanical analysis: DMA 242 E Artemis® Netzsch

DMA 242 E Artemis® Netzsch, Source: IfBB

Dynamic mechanical analysis measures the viscoelastic properties of mostly polymeric materials during a controlled temperature and / or frequency program. During the measurement, a sinusoidal force (stress σ) is applied to the sample, resulting in a sinusoidal strain (strain ε). Polymers show a viscoelastic behavior. They have both elastic (corresponding to an ideal spring) and viscous (corresponding to an ideal damper) properties. Because of this viscoelastic behavior, the deformation (response) is shifted in time from the force (excitation). This deviation is called phase shift δ.

Technical details:

Temperature range: -170 °C to 600 °C
Heating rate: 0.01 to 20 K / min
Frequency range: 0.01 to 100 Hz
High force range: 24 N (12 N static and 12 N dynamic)
Force range with increased resolution: 8 N (4 N static and 4 N dynamic)
Maximum deformation amplitude: +240 μm
Static deformation: up to 20 mm
Module range: 10-3 to 106 MPa
Damping range (tanδ): 0.005 to 100
Cooling devices: Liquid nitrogen, compressed air for cooling down to 0°
Deformation modes: 3-point bend (40mm/50mm)/Pull/Compression/Penetration
Accessories: Immersion bath/UV equipment

Differential Scanning Calorimetry (DDK/DSC): DSC 204 F1 Phoenix Netzsch

Differential Scanning Calorimetry (DDK) or Differential Scanning Calorimetry (DSC) is a thermal analysis method that measures the specific heat of a sample as a function of temperature. Characteristic thermal properties of biopolymers such as melting points, glass transition temperatures and crystallization processes can be determined and graphically visualized using the DSC.

In plastics engineering, this test method is used in the areas of development, production, incoming inspection, quality assurance and damage analysis of molded parts.

Technical details:

Temperature measuring range: -180 °C -700 °C
Heating rate range: 0.001 K/min - 200 K/min
Cooling rate range: 0.001 K/min - 200 K/min
Cooling: max. 200 K / min; automatically controlled liquid nitrogen cooling
Baseline optimization: BeFlat®
Automatic sample changer: DSC 204 F1 Phoenix® ASC for 64 samples and reference cup

Rheology

In the field of rheology, biopolymers and natural fiber reinforced composites are being examined for their deformation and flow behavior. It is equipped with a high-pressure capillary rheometer and an MFR / MVR flow tester to determine the melt density at different temperatures.

High-pressure capillary

Type: "Rheograph 25" from the company Göttfert Werkstoffprüfmaschinen GmbH

Flow behavior of plastic melts according to DIN 54811-A
Bagley and Rabinowitsch-Weißenberg correction
Thermal conductivity measurement according to ASTM D5930
pVT measurement according to ISO 17744

MFR/MVR flow tester

Typ: „Mflow“ der Firma Zwick/Roell

Measurement of MFR and MVR values according to ISO 1133-1
Determination of the melt density at different temperatures

Flow spiral

The flow spiral is a special tool insert for injection molding machines.

Areas of application:

Measurement of the flow path length of thermoplastics
Practical investigation of the flowability of various plastics
Investigation of the influence of fiber and filler contents, mold temperature, injection pressure etc. on rheological properties

Climate change cabinet and UV rapid weathering device

A climate change cabinet and UV rapid weathering device can simulate a wide range of temperature, humidity and UV exposure conditions that can occur throughout the life cycle of a material or component, under extreme conditions and over an accelerated period of time. Here, the long-term resistance to environmental influences and premature aging in the form of embrittlement, blistering and cracking under loss of strength as well as the occurrence of surface damage such as fading, loss of gloss and chalking in the foreground.

The climate test can be carried out according to DIN EN 60068-2-1/-2/-14/-30/-38/-78 and ISO 16750-4. It can be regulated between a temperature of -75 °C to 180 °C and a humidity of between 10 % and 98 %.

Stress due to UV radiation of being exposed to daylight or filtered through a window glass can be measured according to DIN EN ISO 4892-3, DIN EN ISO 16474-3, DIN EN 927-6, ASTM G154, ASTM D4587, ASTM D4329, ASTM D4799, SAE J2020.