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68 The PCB Magazine • April 2016 Results for the average percentage change in weight are illustrated in Figure 6. Weight mea- surements indicate a general trend of increasing weight loss as aging temperature increases in all materials. This indicates that the boards are generally degrading as expected, with oxidation accelerated at higher temperatures. All aged boards showed discoloration to various extents at the end of testing. Laminate A and Laminate E boards also exhibited delamination at higher aging temperatures. It was later discovered that temperatures selected for Laminate E were too high. Figure 7 illustrates the average percentage change in thickness for each laminate. Laminate A had obvious delamination at T3 (185°C) and T4 (195°C). Laminate E showed delamination at all four temperatures tested (220°C, 240°C, 260°C, and 280°C). long-term thermal reliability of pCb materials Table 2: Temperatures Used for 500-Hour Test Based on Tg of material and Supplier's Recommendations. Table 3: Average Breakdown Voltage Time Zero.