Limits RegistryPUBLIC RECORD
Limits RegistryInvar, an iron–36% nickel alloy discovered by Charles-Édouard Guillaume in 1896, has a linear thermal expansion coefficient of about 1.2 × 10⁻⁶/K near room temperature — roughly a tenth that of ordinary steel. Guillaume received the 1920 Nobel Prize in Physics for the discovery.
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Invar, an iron–36% nickel alloy discovered by Charles-Édouard Guillaume in 1896, has a linear thermal expansion coefficient of about 1.2 × 10⁻⁶/K near room temperature — roughly a tenth that of ordinary steel. Guillaume received the 1920 Nobel Prize in Physics for the discovery.
The lowest room-temperature thermal expansion coefficient of a widely used metallic alloy.
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Permanent ID limitsregistry.com/limits/LR-LOWEST-THERMAL-EXPANSION-METAL-ALLOY-INVAR
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Limits Registry. LR-LOWEST-THERMAL-EXPANSION-METAL-ALLOY-INVAR. Lowest thermal expansion of a metallic alloy (Invar). 2026.