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Material Change Similarity
Status Update
IAMFTWG Mobile, Alabama
March 7th, 2017
Rich Lyon, FAATC
Natalia Safronava, FAATC
Daniel Slaton, Boeing
Background:
• MCC was proposed to determine
similarity at the material level when
small changes are made to certified
materials.
• MCC guidance document was
posted on FAA website on June
2016
• Decision flow chart includes 2 MCC
parameters HRC and HR
• The proposed basis for comparing
HRC and HR was the reproducibility
limit from the ASTM D 7309 standard
HRC = HR
∆T
Problem: HR and HRC are not independent
Ignition Capacity
= ≈
HR2 T20W/g
2Tolerance =
Heat Released by Combustion
Heat Needed to Gasify Plastic
HR
T20W/g(°C)
Propose Single MCC Criterion for Small Change (Requires Verification by Industry)
HR = 5.9% ASTM repeatability
T = 1.2% ASTM repeatability
= ±6%
• Heat release (HR) and ignition temperature (≈ T20W/g ) are independent properties
• Both are important for flammability
• Both are easy to measure in MCC
0
0.2
0.4
0.6
0.8
1
100 200 300 400 500 600 700 800 900
Film T004C
on
ver
sio
n,
a
Temperature, C
0.05 Ignition Temperature
Procedure:
Integrate HRR vs time (curve)
Derive by C max (to get 0 to 1 scale)
Find value corresponding to 0.05
Record T
T ign 3020C
0
10
20
30
40
50
60
70
80
100 200 300 400 500 600 700 800 900
Film T004
HR
R, W
/g
Temperature, C
20 W/g
Procedure:
Plot HRR versus T from MCC experiment
Find value corresponding to 20 W/g
Record T
T ign 3250C
Possible methods to determine Tign
Ignition Capacity (HR/Tign) of Common Materials
400 J/g-°C
Heat Release (HR) from:
Principles and Practice of Microscale Combustion Calorimetry, FAA Final Report, DOT/FAA/TC-12/53, R1, April 2013
“Determining Ignition Temperature Using Dynamic Thermal Analysis,” R.E. Lyon et al., Proceedings of the 2017 Fire and Materials
Conference, San Francisco, CA, February 6-8, 2017.
Ignition Temperatures (T20W/g) From:
MCC Data for PC/ABS Blends Large Changes in HRR Signature, HR & Tign
ABS
PC 75% ABS
50% ABS
25% ABS
0/100
25/75
50/50
75/25
100/0
391
394
400
422
503
36.8
32.9
29.2
23.9
19.3
PC/ABS (w/w) Tign(°C)
HR (kJ/g)
Ignition Temperature, Tign
Heat Release, HR
MCC Data for PC/ABS Blends Large Changes in HR and Tign
ABS
PC
75% ABS
50% ABS
25% ABS
MCC Data for PC/ABS Blends Large Changes in HR/Tign
PC/ABS Blends (3-mm) in Cone Calorimeter At 35 kW/m2 External Heat Flux
PC
PC/ABS 75/25
PC/ABS 50/50
PC/ABS 25/75
ABS
• 7 different colors (black, white, red, brown, blue, yellow,
orange)
• 3 different suppliers
• OSU tests results ( pHRR, HR and smoke density ) are
available
• MCC tests results available.
• HR was measured
• Data reanalyzed to obtain Tign = T20W/g
Re-Examine Data from Previous Study to
Substantiate Paint Colors
(Ref. Industry Standardization Task Group Report, 2012)
Paint samples from 2011 study: Set C ( HSN)
OSU
MCC
0
10
20
30
40
50
60
black white blue red yel org yel inorg
pH
RR
0
5
10
15
20
25
30
black white blue red yel org yel inorg
2-m
in H
R
0
10
20
30
40
50
60
70
80
black white blue red yel org yel inorg
HR
/ T
ign
Paint samples from 2011 study
Set A ( Mankiewicz)
0
5
10
15
20
25
black white red brown blue yellow orang
e
pHRR for OSU
pH
RR
0
5
10
15
black white red brown blue yellow orange
2-min THR
2-m
in T
HR
MCC HR/T ign
0
10
20
30
40
50
black white red brown blue yellow orange
HR
/ T
ign
Paint samples from 2011 study
Set D ( MapAero)
0
5
10
15
20
25
30
black white blue red yellow
pH
RR
OS
U
0
2
4
6
8
10
12
black white blue red yellow
2-m
in T
HR
OS
U
0
10
20
30
40
50
60
black white blue red yellow
HR
/ T
ig
n
MCC test results on samples of white paint (2016)
0
10
20
30
40
50
60
70
80
100 200 300 400 500 600 700
Samples 1-5
Sample 1Sample 2Sample 3Sample 4Sample 5
HR
R (
W/g
)
Temperature (C)
Sample HRC sum HRR peak HR T peak T ign (int) T ign (20W/g) HR/T ign
1 150 75 9.0 487 276 366 24
2 148 73 8.5 485 303 384 22
3 151 79 8.8 488 283 313 28
4 144 71 8.5 483 294 383 22
5 140 71 8.6 483 267 383 22
Need OSU results for
comparison
Proposed Next Steps:
New round robin (including low flammability material like
phenolic)
Define standard methodology to define Tig
Modification to ASTM standard to include Tig
Definition of reproducibility limit for HR/Tig