# Enhancing the Accuracy of Advanced High Temperature Mechanical Testing through Thermography
## 3 Results
### Unique Benefits of Thermography  
#### 3.3.1 Test Analysis and Setup  
In comparison to the current methods recommended to control dynamic temperature, thermography has enormous potential. Facilitating the entire specimen gauge section being viewed, monitored and controlled is an exclusive advantage alone to this technique. An additional advantage  
Figure 14: (a) Dynamic temperature turning point response comparison between spot welded thermocouples and thermography area control upon metallic HE23 coated specimen; (b,c) Typical response during the heating and cooling turning points respectively.  
Figure 15: Dynamic peak cycle temperature stability using thermography area control upon ceramic uncoated specimen.  
is that the entire test can be recorded and comprehensively examined post-test. This information could potentially provide additional links uncovering the effects of any identified hot/cold spots with sites of early crack initiation or potential signs towards onset of failure.  
Temperature ranges and modes can be tailored to suit the current objective of the operator, allowing extensive examination of temperature paths and gradients. An example of the comprehensive analysis possible is given in Figure 16. Single point measurements across the specimen gauge section are tracked and recorded in Figure 16a, temperature range is relative to the thermal cycle employed, 800-550 \({}^{\circ}\)C. A more detailed examination of the specimen at the peak cycle temperature of 800 \({}^{\circ}\)C, is shown in Figure 16b. The temperature range has been narrowed to reveal the complex hot and cold spots across a complex ceramic woven structure. Vertical, \(y\)-axis and horizontal \(x\)-axis temperature paths are recorded.  
In the current investigation the thermography technique has proved effective not only to control temperature of both metallic and non-metallic specimens, but during thermal profiling and test setup. An example of a double notched specimen coated with HE23 TP within a complex split transversal electromagnetic field helical induction coil is given in Figure 16c. Typically, it is difficult to achieve uniform temperature distributions during thermal profiling using such a complex electromagnetic field in combination with thermocouples. Moreover, only the small areas captured by the thermocouples can be characterised. Using thermography, thermal distributions were clearly visible and test setups could be adjusted in-situ to achieve the desired temperature distributions. An example of a non-uniform temperature distribution generated by a transversal electromagnetic field is given in Figure 16d. The thermal hot spot is not centred and aligned across the notch gauge sections. Using this technique, a simple adjustment in alignment and position of coil, in-situ, enabled the desired temperature distribution to be achieved.  
Figure 16: Overview of the additional scope and visibility of temperatures thermography can provide. **(a)** Temperature range is relative to the employed 550–800 \({}^{\circ}\)C thermal cycle, single point and area measurements are recorded, through a time/temperature plot; **(b)** Reduced temperature range to uncover intricate temperature maps across the complex ceramic composite material (CMC) structure at the peak cycle temperature, 800 \({}^{\circ}\)C. Line temperature profiles along the specimen \(X\) and \(Y\)-axis are displayed; **(c)** Double notched specimen coated with HE23 TP within a complex split transversal electromagnetic field helical induction coil; **(d)** Non-uniform temperature distribution is clearly visible using thermography across a double notched specimen coated with HE23 TP within a complex split transversal electromagnetic field helical induction coil given in Figure 16c.