TA INSTRUMENTS THERMOMECHANICAL ANALYZER

TA INSTRUMENTSTHERMOMECHANICALANALYZER

TA INSTRUMENTS Q SERIES THERMOMECHANICAL ANALYZERThe Q400 is a sixth-generation product from theworld leader in thermal analysis. Its performance, ease-of-use,and reliability aptly demonstrate our long experience inthermomechanical analysis design.The Q400EM is a high-performance, research-grade thermomechanical analyzer (TMA),with unmatched flexibility in operating modes, test probes, fixtures, and available signals.For standard TMA applications, the Q400 delivers the same performance and reliability.It is ideal for research, teaching, and quality control applications, with performanceequivalent to competitive research models.

TECHNICAL SPECIFICATIONSTemperature Range (max)-150 to 1,000 C-150 to 1,000 C /- 1 C /- 1 C 10 min from 600 C to 50 C 10 min from 600 C to 50 CMaximum Sample Size - solid26 mm (L) x 10 mm (D)26 mm (L) x 10 mm (D)Maximum Sample Size - film/fiber26 mm (L) x 0.5 mm (T)x 4.7 mm (W)26 mm (L) x 0.5 mm (T)x 4.7 mm (W) /- 0.1 % /- 0.1 %15 nm15 nm 1 µm (-100 to 500 C) 1 µm (-100 to 500 C)0.001 to 1 N0.001 to 1 N0.001 N0.001 N0.01 to 2 HzNot AvailableOptionalOptionalInert, Oxidizing,or Reactive GasesInert, Oxidizing,or Reactive Not AvailableCreepIncludedNot AvailableStress RelaxationIncludedNot AvailableDynamic TMA (DTMA)IncludedNot AvailableModulated TMA (MTMA )IncludedNot AvailableTemperature PrecisionFurnace Cool Down Time(air cooling)Measurement PrecisionSensitivityDynamic Baseline DriftForce RangeForce ResolutionFrequencyMass Flow ControlAtmosphere(static or controlled flow)Operational ModesNote: The Q400 can be field upgraded to the Q400EM.

DESIGN FEATURESANDBENEFITSA thermomechanical analyzer measures sample dimensional changes under conditionsof controlled temperature, time, force, and atmosphere. Our engineering experience in designand integration of critical furnace, temperature and dimension measurement, andatmosphere control components meld with powerful, flexible, software to optimize the manytests that the Q Series TMA can perform.1Furnace The Q400 features a rugged and reliablefurnace. Its customized electronics provide excellentheating rate control and rapid response over a widetemperature range. Furnace raising and lowering is software controlled. Benefits: The design ensures long lifeand performance consistency. The excellent heating ratecontrol provides for superior baseline stability andimproved sensitivity, while the rapid response permitsModulated TMA operation. Furnace movementprovides operational convenience, and easy access to thesample chamber.2 Sample Chamber Located in the furnace core, theeasily accessed chamber provides complete temperatureand atmosphere control for sample analysis. Purge gasregulation is provided by an optional digital mass flowcontroller. Benefits: These include enhanced data quality,ease-of-use, and productivity. The open design simplifiesinstallation of available probes (see Modes ofDeformation), sample mounting, and thermocoupleplacement. Data precision is enhanced by mass flowcontrol of the purge gas.12

3Force Motor A non-contact motor provides aprecisely controlled, friction-free, calibrated force tothe sample via the measurement probe or fixture.The force is programmable from 0.001 to 1 N, andcan be increased to 2 N by addition of weights to aspecial tray. A precision sine wave generator provides aset of ten individual frequencies for use in dynamicexperiments. Benefits: The motor smoothly generatesthe accurate and precise static, ramped, or oscillatorydynamic force necessary for quality measurementsin all modes of operation. The choiceof frequencies allows optimization ofdynamic TMA (DTMA) experiments incompression, 3-point bending, or tensionmodes of deformation.124Linear Variable DifferentialTransducer The heart of the Q400TMA sample measurement system is theprecision, moveable-core, linear variabledifferential transducer (LVDT). Benefits:It generates an accurate output signalthat is directly proportional to a sampledimension change. Its precise and reliableresponse over a wide temperature range(–150 to 1,000 C) makes for reproducibleTMA results. Its location below thefurnace protects it from unwantedtemperature effects and ensures stablebaseline performance.34

MODESOFDEFORMATIONThe Q400 offers all the major TMA deformation modes necessary to characterize solids,foams, films, and fibers. These include compression, tension, and 3-point bending.COMPRESSIONIn this mode, the sample is subjected to either a static, linear ramp, or dynamic oscillatory force, while undera defined temperature program, and atmosphere. Sample displacement (strain) is recorded by eitherexpansion / penetration experiments to measure intrinsic material properties, or dynamic tests to determineviscoelastic parameters (DTMA), to detect thermal events, and to separate overlapping transitions(MTMA ).Figure 1EXPANSIONExpansion measurements determine a material’scoefficient of thermal expansion (CTE), glass transition temperature (Tg), and compression modulus.A flat-tipped standard expansion probe (Figure 1) isplaced on the sample (a small static force may beapplied), and the sample is subjected to a temperatureprogram. Probe movement records sample expansionor contraction. This mode is used with most solidsamples. The larger surface area of the macroexpansion probe (Figure 2) better facilitates analysisof soft or irregular samples, powders, and filmsFigure 2PENETRATIONPenetration measurements use an extended tip probeto focus the drive force on a small area of the samplesurface (Figure 3). This provides precise measurementof Tg, softening, and melting behavior. It is valuablefor characterizing coatings without their removal froma substrate. The probe operates like the expansionprobe, but under a larger applied force. The hemispherical probe (Figure 4) is an alternate penetrationprobe for softening point measurements in solids.Figure 3Figure 4

TENSIONTension studies of the stress/strainproperties of films and fibers areperformed using a Film/Fiber probeassembly (Figure 5). An alignmentfixture (Figure 6) permits secure, andreproducible, sample positioning in theclamps. The clamped sample is placedin tension between the fixed andmoveable sections of the probeassembly. Application of a fixed force isusedtogeneratestress/strainFigure 5Figure 6and modulus information. Additionalmeasurements include Tg, softening temperatures, cure, and cross-link density. Dynamic tests (e.g. DTMA,MTMA ) in tension can be performed to determine viscoelastic parameters (e.g., E , E , tan δ), and toseparate overlapping transitions.3-POINT BENDINGIn this bending deformation (also known as flexure), the sample is supported atboth ends on a two-point, quartz anvil atop the stage (Figure 7). A fixed staticforce is applied vertically to the sample at its center, via a wedge-shaped, quartzprobe. Material properties are determined from the force and the measured probedeflection. This mode is considered to represent “pure” deformation, since clamping effects are eliminated. It is primarily used to determine bending properties ofstiff materials (e.g., composites), and for distortion temperature measurements.Dynamic (DTMA) measurements are also available with the Q400EM, where aspecial low-friction metallic anvil replaces the quartz version.Figure 7SPECIALTY PROBE / FIXTURE KITSAdditional sample measurement probes and fixtures are available for use with both the Q400 and Q400EMin specialty TMA applications. These include:Dilatometer Probe Kit – for use in volume expansion coefficient measurementsParallel Plate Rheometer – for the measurement of low shear viscosity of materials (10 to 107 Pa.s range)under a fixed static force.The expansion, macro-expansion, and penetration probes are supplied with the Q400. These probes, plus theflexure probe, and the low-friction bending fixture, are included with the Q400EM module. Data analysisprograms relevant to each of the measurements described are provided in our Thermal Advantage forQ Series software.

TMA THEORYTMA measures material deformation under controlled conditions of force, atmosphere, time, andtemperature. Force can be applied in compression, flexure, or tension modes using probes previouslydescribed. TMA measures intrinsic material properties (e.g., expansion coefficient, glass transition temperature,Young’s modulus), plus processing / product performance parameters (e.g., softening points). These measurements have wide applicability, and can be performed by the Q400/Q400EM.TMA can also measure polymer viscoelastic properties using transient (e.g., creep, stress relaxation) ordynamic tests. These require the Q400EM module. In creep, a known stress is applied to the sample, and itsdeformation is monitored. After a period, the stress is removed, and strain recovery is recorded. In stressrelaxation, a fixed strain is applied, and stress decay is monitored.In Dynamic TMA (DTMA), a knownsinusoidal stress and linear temperature rampare applied to the sample, and the resultingsinusoidal strain, and sine wave phasedifference (δ), are measured (Figure 8). Fromthis data, storage modulus (E ), loss modulus(E ), and tan δ (E /E ) are calculated asfunctions of temperature, time, or stress.FIGURE 9Modulated LengthModulated TemperatureTTemperatureFIGURE 8In Modulated TMA (MTMA ), the sampleexperiences the combined effects of a linear ramp, and asinusoidal temperature of fixed amplitude and period(Figure 9). The net signals, after Fourier transformationof the raw data, are total displacement and change inthermal expansion coefficient. Both can be resolved intotheir reversing and non-reversing component signals.The reversing signals contain events attributable todimension changes, and are useful in detecting relatedevents (e.g., Tg). The non-reversing signals contain eventsthat relate to time dependent kinetic processes (e.g., stressrelaxation).

MODESOFOPERATIONThe Q400 and 400EM operating modes permit multiple material property measurements.The Q400 features the Standard mode, while the Q400EM additionally offers Stress/Strain,Creep, Stress Relaxation, Dynamic TMA, and Modulated TMA modes.STANDARD MODE (Q400/Q400EM)Temperature Ramp: Force is constant, and displacement is monitored undera linear temperature ramp. Provides intrinsic property measurements.Strain (Force)TForceStrainIsostrain: Strain is constant, and the force required to maintain it isTemperature (Time)monitored under a temperature ramp. Permits assessment of shrinkage forces infilms/fibers.StrainForce Ramp: Force is ramped, and strain measured at constant temperature toFTgenerate force/displacement plots, and modulus information.Force (Time)STRESS/STRAIN MODE (Q400EM)Stress (Strain)StrainStressStress or strain is ramped, and the resulting strain or stress is measured atconstant temperature. Both provide stress / strain plots and related modulusinformation.TStrain (Stress)In Creep, stress is held constant, and strain is monitored. In Stress Relaxation,strain is held constant, and stress decay is monitored. Both are transient testsused to assess material deformation and recovery properties.Strain / StressCREEP/STRESS RELAXATION MODES (Q400EM)t1t2DYNAMIC TMA MODE (Q400EM):T% StrainTimeSA sinusoidal force (stress) is applied during a temperature ramp. Analysis ofthe resulting strain and phase data provides viscoelastic property parameters(e.g., E , E tan δ).MODULATED TMA MODE (Q400EM):Modulated LengthTemperature is programmed linearly, and simultaneously modulated at constantstress to generate signals relating to total displacement, CTE, and their reversingand non-reversing components. These permit detection of thermal transitions,and separation of overlapping events (e.g., Tg and stress relaxation).TTemperatureModulated TemperatureTemperature (time)