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Invar

All articles tagged with #invar

science-and-technology2 years ago

The Mystery Unveiled: The Reason Behind Non-Expanding Alloys Revealed

Scientists have finally discovered why certain alloys, such as Invar, do not expand when heated. These alloys, which contain specific ratios of iron and other metals like nickel, exhibit an exception to the general rule that materials expand when heated. The researchers found that magnetism plays a crucial role in balancing out the entropy caused by heat, preventing the atoms in the alloy from moving further apart. This understanding could have applications in precise instrument manufacturing and infrastructure building, where heat-sensitive metals can cause problems. The study improves our understanding of thermal expansion in other magnetizable materials.

science-and-technology2 years ago

Unveiling the Mystery: Why Some Alloys Remain Unchanged When Heated

Researchers from the California Institute of Technology have discovered the secret behind the unusual behavior of Invar alloys, which do not change in size and density over a wide range of temperatures. By measuring the vibrational spectra and magnetism of Invar samples, the researchers found a delicate balance between thermal expansion caused by atom vibrations and magnetism. The interaction between vibrations and magnetism, such as altered frequencies of atom vibrations, helps maintain this balance. This finding could aid in understanding thermal expansion in other magnetic materials and developing materials for magnetic refrigeration.