Thermomechanical Process Modelling of 40NICRMO8-4 Alloy by ...
Thermomechanical Analysis (TMA)TMA: The Technique • Thermomechanical Analysis measureschanges in...
Transcript of Thermomechanical Analysis (TMA)TMA: The Technique • Thermomechanical Analysis measureschanges in...
Thermomechanical Analysis (TMA)熱機械分析儀,原理與應用
許炎山TA Instruments, Waters LLC
美商沃特斯國際股份有限公司台灣分公司
TA Taipei office: 104臺北市長安東路1段23號4F之5
Tel: 02-25638880 Fax: 02-256388700928-168676
逢甲大學校本部商學大樓8樓第八國際會議廳2016年8月5日(五)
TMA: The Technique
• Thermomechanical Analysis measureschanges in the dimensions of a sample as a function of time, temperature and force in a controlled atmosphere.
• TMA can measure Coefficient of Thermal Expansion (CTE), along with transitions like Tg
• Can also make viscoelastic measurements
TMA: What TMA Can Tell You
Compatibity of materials that must function together: e.g., coatings and their substrates, adjacent layers of laminates, resins or elastomers and their reinforcements or fillers, seals or encapsulants and the mechanical systems they protect
Suitability of materials for use in harsh environments and temperature extremes: e.g., brake linings, automotive gaskets, window seals, solder joints, adhesives, and protective coatings
TMA: What TMA Can Tell You
Physical characteristics and mechanical properties of materials, including films and fibers
Optimum processing conditions for manufacturing efficiency, economy and product quality, including the ability to monitor rate and degree of cure of polymers
熱性質與狀態改變(1)First-Order Transition
ΔG=ΔH-TΔS
熱性質與狀態改變(2)
ΔG=ΔH-TΔSSecond-Order Transition
α1
α2
Cp1
Cp2
Q400 TMA (EM)
TMA 2940/Q400/Q400EM Key Schematic
Furnace
FurnaceAssembly
Stage
LVDT
SuspensionAssembly
Force CoilAssembly Shuttle
Stepper Motor
FurnaceLift Motor
LeadScrew
Sample
Probe
CoolantReservoir
樣品內置與外放的比較
內置
外放
TMA: Types of probes
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• Compression• Expansion• Penetration• Dilatometry• Parallel Plate Rheometry• Flexure
•Tension•Films and Fibers
TMA: Common Probes
Standard Expansion
Macro Expansion
Penetration Hemispherical
Expansion Penetration
• Measures:• Coefficient of Thermal Expansion (CTE)• Glass Transition Temperature• Compression Modulus of Polymeric Materials
• The flat tipped standard probe is used for most solid materials
• The macroexpansion probe (larger surface area) is more effective for soft or irregular samples, powders, frozen liquids, and films
TMA: Expansion Probes
TMA: Penetration Probes
• Measures:• Softening and Melting Points• Coating and Film Evaluation
• An optional probe with a hemispherical tip offers an alternate means for obtaining softening point data
TMA: Less Common Probes
Film/Fiber Tension Three-Point Bend
TMA: Flexure (3-P-B) Probe and Stage
Knife-EdgedLoading Nose
Knife-EdgedSupports
Sample
LOAD
Sample Length =5.08 mm (0.2 in.)
Measures the deflection (bending) properties of stiff materials such as laminates and composites
The sample rests on a two-point anvil positioned on the stage, while a wedge-shaped probe applies force
TMA: Film/Fiber Probe (Old)
FILM CLAMPRELIEF NOTCHAT TOP
STRAIGHT EDGEAT BOTTOM
FILM SAMPLE
STRAIGHT EDGEAT TOP
FILM CLAMPRELIEF NOTCHAT BOTTOM
Film FiberTension
TMA: Q400 Film/Fiber Probe (New)
Flange to keep clamp from rocking
TMA: Low-Friction Al Fixture
The low-friction aluminum fixture consists of an aluminum three-point bend platform with two rollers spaced 10.16 mm apart. It is not recommended for use in thermal expansion experiments
TMA: Equations for Estimation of Flexural Stress, Strain, Modulus
S = 3PL2bd2
r = 6DdL2E = s/r = PL
4bDdb
3
3
S = Stress, MPa (psi) L = Span, mm (in.)r = Strain, mm/mm (in./in.) b = Width, mm (in.)Eb= Modulus of Elasticity, MPa (psi) d = Depth, mm (in.)P = Load, N (lbf) D = Deflection of Mid-Span, mm (in.)
TMA: Sample Preparation andOperating Conditions
• Sample Preparation• Bulk Samples - parallel faces for expansion
- reasonably flat for penetration• Films/Fibers - cut and mount using fixture
- use razor to avoid tears/cracks
• Force (maximum programmable is 1.0N)• Expansion - low force (0.001N to 0.05N)
(0g to 5g)• Penetration - higher force (0.05N to 0.5N)
(5g to 50g)
TMA: Sample Preparation and Operating Conditions
• Heating Rates• Use slow heating rates to prevent thermal
gradients (< 5°C/min)
• Purge Gas• Below 300°C - Helium is used because of
excellent thermal conductivity• Above 300°C - Nitrogen is used (helium will
overwork furnace at higher temperatures)• Flow Rate = 100mL/min.
Mechanical Cooling Accessary MCA 70
Uses the RCS90 compressor system Redesigned heat exchanger Faster Cooling MUCH less frosting Auto-recognition Event control capability
Thermomechanical Analysis(TMA)
Applications
TMA and The Concept ofFree Volume
自由體積Free Volume
IPC-TM-650 2.4.24.5 Glass Transition Temperature and Thermal Expansion of Materials Used
in High Density Interconnection (HDI) and Microvias - TMA Method
Method AVolumetric or Z-axis expansion – thick specimens (>0.50 mm): Method BIn-plane (x-y) expansion – thin specimens (<0.5mm):
內應力的生成
分子取向
未ラビング
複屈折:小
ラビング
複屈折:大 複屈折の立体的な評価
液晶配向膜:ラビング 光学位相フィルム 光ディスク基板
TMA: Schematic Diagram ofThermal Expansion Mismatch
A.M./ Ibrahim, etal. inMaterials Characterization by Thermomechanical Analysis,ASTM STP,1136, A.R. Riga and C. M. Neag, Eds., ASTM, Phila., (1991), pp 161-167
Leadless CeramicChip Carrier (LCCC)CTE 5.9-7.4 ppm/°C
PCB Substrate(fabric/resin composite)CTE 12-16 ppm/°C
StressedSolderJoints
TMA: CTE MismatchThermal Stress (熱應力)的評估
A.M./ Ibrahim, etal. inMaterials Characterization by Thermomechanical Analysis,ASTM STP,1136, A.R. Riga and C. M. Neag, Eds., ASTM, Phila., (1991), pp 161-167
Leadless CeramicChip Carrier (LCCC)CTE 5.9-7.4 ppm/øC
PCB Substrate(fabric/resin composite)CTE 12-16 ppm/℃
StressedSolderJoints
σ=Eαl (To-Tf)E: modulus of elasticityαl (To-Tf)= ε ,ε:thermal strain
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TMA: CTE Versus % Cure for SMC
93 94 95 96 97 98 99 10055
60
65
70
75
80
85
Percent Cure
CLT
E (p
pm/C
)R. D. Adams in Materials Characterization by Thermomechanical Analysis, ASTM STP, 1136, Riga and Neag Eds., ASTM, Phila. (1991) pp 150-160
研發舉例
A. 增加樹脂的Tg B. 增加填充物的含量
TMA: Expansion Measurements
•Expansion Coefficient
•Glass Transition
•Delamination/Decomposition
TMA: Coefficient of Thermal Expansion
• Coefficient of Thermal Expansion (CTE)• Quantitative measurement of change in length(∆ L) with change in temperature (∆T)
• Important in many applications but especially in composite structures
• Results can vary significantly with samples having oriented structure due to processing (tension, pressure, cooling rate, etc.)
• High accuracy/reproducibility usually obtained with samples >5mm thick
TMA: Definition of Coefficient of Thermal Expansion CTE (
Differential or point definition
Slope definition
= 1L
dLdTo
= 1L
LTo
Cell Constant
The cell constant in TMA is typically ran with Aluminum in Calibration modeThis works well for most materials (typical polymers) ran in the compression or tensile modeWhen the materials CTE gets too low (below 5 µm/(m°C), the error increasesASTM E831 refers to this
Materials with lower CTE’s can be measured if an appropriate material is used for calibration of the cell constantTo do this the cell constant must be calculated manually
Expansion of 7.6 mm Aluminum Standard
TMA: Expansion of 0.25mmDiameter Aluminum Wire
0 50 100 150 200 250 300 350 400 450-10
0
10
20
30
40
50
60
70
80
90
TEMPERATURE (°C)
DIM
ENSI
ON
CH
AN
GE
(mm
)
+227.0°Ca = 20.4mm/m°C
+ 77.0°Ca = 20.4mm/m°C
Calibration Constant(K = 1.22)
Fiber Probe
Prog: 10°C/minSize: 10 mm
Coefficient of Thermal ExpansionCalculation Methods
at X
X1 to X2
Fit X1 to X2
TMA: Polyimide Film
20 40 60 80 100 120 140 160-5.3
-5.2
-5.1
-5.0
-4.9
Temperature (°C)
Dim
ensi
on C
hang
e (m
m)
74.98°C
113.16°Ca = 71.3m/m°C
TMA measurement for Low CTE Materials
©2013 TA Instruments
= 1L
dLdTo
石英
Cell Constant
Data
The data on the following slides were run with a cell constant of 1The data were analyzed and cell constant’s calculatedThe data were re-analyzed with the appropriate cell constants.
Aluminum Before Calibration
58.66°C
149.45°CAlpha=22.58µm/(m·°C)
Ran and Analyzed with a cell constant of 1
Based on a CTE of 23.6µm/(m°C)
Size: 23.9771 mm
-50
0
50
100
150
Dim
ensi
on C
hang
e (µ
m)
-50 0 50 100 150 200
Temperature (°C) Universal V4.5A TA Instruments
Aluminum After Calibration
Ran with cell constant of 1Analyzed with cell constant of 1.04 in UA
58.66°C
149.45°CAlpha=23.48µm/(m·°C)
Based on a CTE of 23.6µm/(m°C)
Size: 23.9771 mm
-50
0
50
100
150D
imen
sion
Cha
nge
(µm
)
-50 0 50 100 150 200
Temperature (°C) Universal V4.5A TA Instruments
Platinum Before Calibration
40.00°C
125.00°CAlpha=10.89µm/(m·°C)
Ran and Analyzed with a cell constant of 1
.84
Based on a CTE of 9.18µm/(m°C)
Size: 7.9578 mm
-4
-2
0
2
4
6
8
10
Dim
ensi
on C
hang
e (µ
m)
0 20 40 60 80 100 120 140 160
Temperature (°C) Universal V4.5A TA Instruments
Platinum After Calibration
40.00°C
125.00°CAlpha=9.149µm/(m·°C)
Ran with cell constant of 1Analyzed with cell constant of 0.84 in UA
Size: 7.9578 mm
Based on a CTE of 9.18µm/(m°C)
-2
0
2
4
6
8D
imen
sion
Cha
nge
(µm
)
0 20 40 60 80 100 120 140 160
Temperature (°C) Universal V4.5A TA Instruments
Tungsten Before Calibration
Ran and Analyzed with a cell constant of 1
Based on a CTE of 4.6µm/(m°C)
Size: 24.0338 mm
25.00°C
150.00°CAlpha=1.865µm/(m·°C)
18
20
22
24
26
28
30D
imen
sion
Cha
nge
(µm
)
-50 0 50 100 150 200
Temperature (°C) Universal V4.5A TA Instruments
Tungsten After Calibration
Ran with cell constant of 1Analyzed with cell constant of 2.47 in UA
Size: 24.0338 mm
Based on a CTE of 4.6µm/(m°C)
25.00°C
150.00°CAlpha=4.606µm/(m·°C)
45
50
55
60
65
70
75D
imen
sion
Cha
nge
(µm
)
-50 0 50 100 150 200
Temperature (°C) Universal V4.5A TA Instruments
Conclusions of CTE measurement
TMA can be used for low CTE materials, but to get the best accuracy a cell constant with a similar expansion should be usedThe instrument can be run with a cell constant of one, and the correct value entered when opening the file in UAThis allows post test implementation for the correct cell constant which gains additional flexibility for the user