Answer to Question 1
Three ways that an exotherm can be controlled during casting include air, water, and pressure. Higher pressure causes the foam to cure slower, so the higher the pressure that is within the cast, the more control you have. Also water and air help cool the exotherm to aid in creating a better part with less cracking capabilities. Cooling the exotherm also causes it to cure slower.
Answer to Question 2
Some advantages are cost benefits, cheaper molds and materials. They also have low thermal conductivity and can enhance the strength of a part when it is placed between two materials. A smaller shot size is used in injection molding, also requiring less plastics material to fill the mold. The chemical reaction that creates the foam requires less mechanical heat and pressure from the machine.
The work of Charles Darwin forms the foundation for modern evolutionary theory.
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