Thermal Expansion Properties of Fe-42Ni-Si Alloy Strips Fabricated by Melt Drag Casting Process

摘要

Thermal expansion property was investigated on Fe-42 percent Ni alloy strip added by alloying element of Si of 0-1.5 wt. percent. The strip was fabricated by a melt drag casting process. Addition of Si enlarged the solid-liquid region and reduced the melting point which leads to the increase of the formability of a strip. The alloy containing 0.6 wt. percent Si showed the lowest thermal expansion ratio in the temperature range between 20 to 350 deg C. The grain size was increased with reduction ratio and annealing temperature, which resulted in the decrease of the thermal expansion coefficient of strip. Because of grain refining by precipitation of Ni_3Fe, the alloy strip containing 1.5 wt. percent Si showed higher thermal expansion ratio compared with the alloy containing 0.6 wt. percent Si.