|MadSci Network: Engineering|
Assuming you formed the ceramic around the spring while it was under tension, and then melted the spring while it was under tension, the whereabouts of the tension is not an issue to be concerned with. The difficulty has to do with deciding what is under tension. When you chose to form a ceramic around your spring, which was already under tension, you introduced an contact surface between the ceramic and the spring. While the spring and the tension are unchanged there are no forces, compression or tension, between the spring and the ceramic. If the tension is increased, compression occurs between the ceramic and the spring to oppose the change and there may be minor tensile forces depending upon the extent to which the ceramic and spring materials adhere. If the tension is decreased, compressive and tensile forces occur again, though oriented in the opposite directions. For the case where the tension is unchanged and the spring is melted, the connection to the mass (or the basis of the original tension) will be severed at or near the surface of the ceramic and there is no basis for compressive or tensile forces between the ceramic and the melted spring. In essence, when you formed a ceramic about your spring, you no longer had a spring, in the usual sense. The best references are still high school and college physics textbooks, though you may not find your specific question addressed there. Introductory materials textbooks might also give you background on the sort of environment imposed when the ceramic was formed about the spring. Thanks for your question. sid
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