Science, Maths & Technology
Engineering: The challenge of temperature
...LAS, which crystallises in hexagonal planes of atoms leading to a curious response to heat. Its expansion coefficient depends on direction within the crystal: +6.5 × 10−6 K−1 in the plane of the hexagon and −2.0 × 10−6 K−1 perpendicular to the hexagon. Yes – a negative coefficient of expansion. As the atoms spread sideways the layers can pack down into their...