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This incredible shrinking material is called cubic zirconium tungstate (alpha-ZrW2O8).  When you turn up the heat on most materials the increased energy causes the atoms to move around more. The atoms need more space to move in so the material expands. A few maverick materials do the opposite and shrink as you heat them. This is called negative thermal expansion and it usually occurs over a relatively small temperature range. For example liquid water becomes more dense as its temperature rises but only until it reaches about 4 C. Because of zirconium tungstate’s unique structure it continues to shrink even at extremely high temperatures.  Coming to a mouth near you
Scientist are looking at zirconium tungstate to see if it can be used in materials to make everything from bridges to electronics. If you have fillings you could personally benefit. When you drink something warm like hot chocolate your fillings expand, when you eat something cold like ice cream they contract. All this expansion and contraction can leave you with cracked fillings. Scientists are blending zirconium tungstate with materials that expand normally to see if they can come up with a new filing material that doesn’t expand or contract.
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