TOOLED THICK COMPOSITES by ARVEN H. SAUNDERS III ...

Temperature (C)
200
180
160
140
120
100
80
60
40
20
S2/8552 Flexbeam Model
0
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 1680 1800 1920 2040 2160 2280 2400 2520
Time (min)
Figure 4.6. Acceptable S2/8552 Flexbeam Temperature Cycle.
57
ToolTemp
MinLamT
MaxLamT
MaxTDelta
constraints, the next temperature setpoint is reduced, and so on for each next minute. This is
equivalent to having many more individual temperature stages using the Rai model.
The groundrules that were specified for temperature optimization served as basic rules
or constraints applied to the self-directed control approach to find a reasonable optimum cure
process. Thus the constraints act as rules that guide the “controller” at each timestep, effectively
paring down the optimum domain space by eliminating from consideration those values that
would violate the constraints. While not guaranteed to be the global (which is improbable)
optimum, it is assured to be a local optimum cure process.
For the 3501-6 flexbeam laminate, a similar course of action was followed, in order to
arrive at an acceptable temperature cycle, subject to the same constraints of maximum
temperature and maximum temperature difference within the laminate. These results are
presented in Figure 4.7. Note that the total process time to complete the 177°C dwell is 35
hours, less than the S2/8552 flexbeam laminate.