Copper-coated, epoxy-filled fiberglass circuit boardsare

Chapter 5, Problem 5.45

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Copper-coated, epoxy-filled fiberglass circuit boardsare treated by heating a stack of them under highpressure, as shown in the sketch. The purpose of thepressingheating operation is to cure the epoxy thatbonds the fiberglass sheets, imparting stiffness to theboards. The stack, referred to as a book,is comprised of10 boardsand 11 pressing plates,which prevent epoxyfrom flowing between the boards and impart a smoothfinish to the cured boards. In order to perform simpli-fied thermal analyses, it is reasonable to approximatethe book as having an effective thermal conductivity (k)and an effective thermal capacitance (?cp). Calculatethe effective properties if each of the boards andplates has a thickness of 2.36 mm and the followingthermophysical properties: board (b) ?b?1000 kg/m3,cp,b?1500 J/kg?K, kb?0.30 W/m?K; plate (p) ?p?8000 kg/m3, cp,p?480 J/kg?K, kp?12 W/m?K.