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APRIL 2018 I SMT007 MAGAZINE 75 decision tree that can determine which mate- rial can be used for a specific application. The description as well as motivation to perform each test is below. Thermal Mechanical Analysis This test is performed to check the dimen- sional stability of a test specimen as well as calculate its Tg. The results of this test are important because they will indicate how the 3D printed specimen maintains its dimen- sional stability. For materials to be used in PCBA processes, all auxiliary components must retain their mass as well as dimensional accuracy. Thermal Gravimetric Analysis Thermal gravimetric analysis is performed to determine the temperature when the material, in this case, the test specimen, has lost 5% of its weight. For this study, the temperature used was 300°C. The results taken from this test help indi- cate the lifespan of a material, the faster it loses its weight, its lifespan decreases. Thermal Life Cycle Test For this test, the 3D printed test specimens were subjected to 200 cycles of a predeter- mined temperature profile. Each cycle was the same in duration of time. The results of this test show what happens to a 3D printed test specimen when subjected to high temper- atures. Any indication of warpage, delami- nation, degradation or other visible and/or cosmetic damage is important to capture. The results from this test indicate which materials are suited for high temperature applications in the PCBA process. Density Test This test is a calculation based on the vari- ous parameters of a test specimen. The density was checked after thermal and chemical resis- tance testing. The results of this test are used to determine how well the test specimen can hold its mass after being subjected to either chem- ical or thermal stresses. The density check of test specimens helps determine which applica- tion it is suited for. Figure 1: Thermal mechanical analysis results. Figure 2: Thermal gravimetric analysis results. Figure 3: Thermal life-cycle test results.