Thermal Analysis Methods (Part 1): TG, DSC, STA, EGA

Thermal effects Dielectr. Thermal Mass changes Dimensional from physical constant Conductivity due to changes, and chemical (permittivity), Thermal evaporation, deformations, processes loss factor, Diffusivity decomposition viscoelastic (phase conductivity, Specific Heat and interaction properties, transitions, resisitivity Thermal with the transitions, reactions); (ion viscosity); Expansion atmosphere density specific heat cure index (degr. of cross-linking) Evolved Gas Analysis (EGA – MS, FTIR, GC-MS)

Krakow 2012/ep www.netzsch.com Thermogravimetric Analysis

With this Instrument were obtained the first TG-curves for

MnSO4• H20, CaCO3 and CrCO3.

First thermobalance were built by Kotaro Honda in 1915, working at Tohoku Imperial University.

Krakow 2012/ep www.netzsch.com Thermogravimetry (TG): Measuring Principle

Background:

- law of mass conservation - mass change by reaction separation/absorption of gaseous materials  transition rate = f(m)

.Electronic microbalance – the sample’s gravitational force is continually evened out by the electromagnetic force.

.The needed current for the equilibrium represents the measurand and is recorded. .ASTM E 473 – 85: .Thermogravimetry is a technique in which the mass of a substance is measured as a function of temperature while the substance is subjected to a controlled-temperature program.

Krakow 2012/ep www.netzsch.com Arrangements of Commercial TGAs

Krakow 2012/ep www.netzsch.com Schematic of a Top Loading Balance

gas outlet

cover support

sample

sample carrier cooling gas inlet vacuum purge

cooling

pressure sensor hoist sample carrier relief valve balance gas inlet protective

Krakow 2012/ep www.netzsch.com TG curve

TG /%

100 -12.05 % 90

80 -18.81 % 70

60 -29.48 % 50

30 100 200 300 400 500 600 700 800 900 Temperature /°C

Krakow 2012/ep www.netzsch.com TG and DTG curves

TG /% DTG /(%/min)

100 1.0 -12.05 % 90 0

80 -1.0 -18.81 % 70 -2.0

60 -3.0 -29.48 % 50 -4.0

40 -5.0

30 -6.0 100 200 300 400 500 600 700 800 900 Temperature /°C

Krakow 2012/ep www.netzsch.com Stainless Steel in Humid Atmosphere

2 days isothermal at 900°C

Sample: Stainless Steel Sample mass: ~ 500 mg Crucible: Alumina Plate Heating rate: 10/0 K/min Atmosphere: Water vapor Sensor: TG type S

Krakow 2012/ep www.netzsch.com Differential Scanning Calorimetry / Differential Thermal Analysis

Furnace Sample Refer. . QPR

T

Differential Scanning Calorimetry (DSC) is a Thermal Analysis technique in which the heat flow rate (power) to the sample is monitored against time or temperature while the temperature of the sample, in a specified atmosphere, is programmed ICTA; For better Thermal Analysis and Calorimetry, Edition III (1991)

Krakow 2012/ep www.netzsch.com DTA and DSC Principle

During a phase transition a temperature difference (heat flux difference) between the sample and reference can be measured by means of a thermocouple.

Krakow 2012/ep www.netzsch.com Generation of the DSC/DTA Signal

Krakow 2012/ep www.netzsch.com Magnesium Alloy

Krakow 2012/ep www.netzsch.com Second Order Phase Transitions - magnetic phase transition of iron (Lambda shape) -

DSC /(mW/mg) Sample: Iron disk exo Sample mass: 129.68 mg 7 Crucible: Pt+liner+lid Sample holder: DSC-cp Heating rate: 20 K/min 6 Atmosphere: Argon at 50 ml/min 1559.7 °C 5 Sample: Iron 4

3 266.1 J/g

2 1399.3 °C 926.4 °C 1 770.2 °C 16 J/g 16.13 J/g 0 1534.0 °C magnetic A3 A 4 melting -1 200 400 600 800 1000 1200 1400 1600 Temperature /°C

Krakow 2012/ep www.netzsch.com Phase diagrams - DSC

Krakow 2012/ep www.netzsch.com Phase diagram of NiAl

Krakow 2012/ep www.netzsch.com Heat Capacity of Molydenum

0.40

Mo: Literature Mo: Measurement 0.35

0.30

0.25 Specific Heat /J/(g Heat Specific K)

0.20

0.15 -200 -100 0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 Temperature /°C

Krakow 2012/ep www.netzsch.com Simultaneous Thermal Analysis (STA)

Simultaneous Techniques

This refers to the application of two or more techniques to a (single) sample at the same time. A hyphen is used to separate the appreviations, e.g. simultaneous thermogravimetric analysis and differential scanning calorimetry (TGA-DSC). ICTA 1991

TG-DSC/DTA

Simultaneous mass change and energetic information on one and the same sample under absolutely identical measurement conditions

Krakow 2012/ep www.netzsch.com Simultaneous Thermal Analysis (STA)

Furnace Sample Refer. . QPR

T

TG + DSC = STA Thermogravimetry Differential Scanning Calorimetry

TG, DSC applied simultaneously to the same sample.

Krakow 2012/ep www.netzsch.com TG – DSC Measurement of Fe2O3

Krakow 2012/ep www.netzsch.com Heating and Cooling of MnO2

TG /% DSC /(mW/mg) exo 102

-0.23 % 6 100

619.1 °C

98 4

958.2 °C 96 Sample: MnO2 1200.7 °C -9.20 % 2 71.45 J/g 94

432.1 J/g 179.7 J/g 0 92 -71.83 J/g

90 1147.8 °C -2 -3.07 %

-4

86 200 400 600 800 1000 1200 1400 Temperatur /°C

Krakow 2012/ep www.netzsch.com Different Furnaces for Different Applications

Krakow 2012/ep www.netzsch.com Sample Carriers

TG-DSC

TG-DTA TG

TG-DSC- cp

Krakow 2012/ep www.netzsch.com Special STA furnaces increase application range

2400°C Furnace

Water Vapour Furnace

Krakow 2012/ep www.netzsch.com Scheme of the Tungsten Furnace

Maximum temperature at sample: 2400°C

Maximum heating and cooling rate: 100 K/min

Atmospheres: Helium, vacuum

Krakow 2012/ep www.netzsch.com Tungsten Furnace Guarantees very clean Atmospheres

At 2400 °C, the vapor pressure of graphite is 10-3 torr, therefore no high vacuum can be applied. The tungsten furnace of the STA 429 allows measurements in high vacuum (10-5 torr) up to 2400 °C. This is essential for clean atmospheres and Knudsen cell tests

Krakow 2012/ep www.netzsch.com Melting and Crystallization of Vanadium

TG /% DTA /(µV/mg) [1.2] 120 sample Vanadium, 20 K/min, He 7 exo

100 6 theoretical values: melting1890°C 38.47 µVs/mg

80 1887.1 °C 5 heating 60

4 40 cooling 1879.9 °C

Temperature program: RT to 1970°C to 1600°C -38.74 µVs/mg 3 20 Heating rate: 20 K/min Atmosphere: He

Crucible: ZrO2 „liner“ in W crucibles 0 2 1760 1780 1800 1820 1840 1860 1880 1900 1920 1940 Temperature /°C Main 2009-07-03 08:08

Krakow 2012/ep www.netzsch.com Created with NETZSCH Proteus software Sapphire

TG /% DTA /(µV/mg) exo 100 Temperature range: RT to 2100°C 12 50 Heating rate: 75 K/min

Crucible: W with lid 11 0 Atmosphere: He Sample weight: 12.34 mg 52.43 µVs/mg -50 10

Melting of Sapphire -100 9 2nd heating -150 8

-200 2055.0 °C

7 -250

-300 6 2000 2020 2040 2060 2080 2100 Temperature /°C Main 2009-07-03 12:01

Krakow 2012/ep www.netzsch.com Created with NETZSCH Proteus software EGA methods combined with TGA

. MS Mass Spectrometry

. FTIR Fourier Transform Infrared Spectroscopy

. GC-MS Gas Chromatography with MS

. GC-FTIR GC with FTIR

www.netzsch.com Krakow 2012/ep MS Capillary Coupling

Krakow 2012/ep www.netzsch.com Hydromagnesite (STA-MS Capillary)

Mg5(CO3)4 (OH)2 * 4 H2O

mass 25.98 mg temp. 25 ... 960°C HR 10 K/min Air, 80 ml/min

www.netzsch.com Krakow 2012/ep 16th March 2011

Krakow 2012/ep www.netzsch.com Tools to Investigate such Events?

Krakow 2012/ep www.netzsch.com Zircaloy Zirc-4 BCR-276

DTG /(%/min) TG /% Ion Current *10-9 /A

5.0 0.8 114 TG 0.7 112 4.0 BCR-276 0.6 110 in N2 and water vapor atmosphere 0.5 DTG 5 K/min 3.0 108 0.4 106 2.0 0.3 104 0.2

102 2 amu 1.0 0.1

100 0.0 0 500 600 700 800 900 1000 Temperature /°C

Krakow 2012/ep www.netzsch.com MS-Skimmer Coupling

Quadrupol analyzer 10 -5 mbar Ion source

10 -1 mbar

Skimmer Orifice

Sample r

a Heater

3 1

0 Sample carrier 1

Gas overflow

Krakow 2012/ep www.netzsch.com Melting behaviour of CuGaSe2

http://www.nrel.gov/docs/fy03osti/33997.pdf NREL/SR-520-33997

Krakow 2012/ep www.netzsch.com CuGaSe2

Impurities: Selenium excess, Iodine

Krakow 2012/ep www.netzsch.com STA – MS – FTIR Coupling

Krakow 2012/ep www.netzsch.com TG – FTIR Measurement of PVC

www.netzsch.com Krakow 2012/ep STA – GC – MS Coupling

Krakow 2012/ep www.netzsch.com Thank you for your attention

Krakow 2012/ep www.netzsch.com