Study on Microstructure，Texture and Mechanical Properties of Strip Casting Invar Alloy

doi:10.12068/j.issn.1005-3026.2020.05.019

Abstract

Abstract: The twin-roll strip casting technology was introduced into the process of manufacturing invar alloy. Using optical microscope， XRD， EBSD， micro hardness(HV) and tensile testing instruments， the evolution of microstructure， texture and mechanical properties of the strip-casted invar alloy were investigated. The results show that the solidification microstructure of the strip-casted invar alloy is dominated by the coarse columnar grains of austenite and the associated texture is mainly the strong λ-fiber texture(<100>//ND). Thereafter， a large amount of deformation substructures are formed during a cold-rolling process， which increase the hardness(HV) from 165 to 230~240， and the cold-rolled texture is mainly composed by the typical copper texture (112<111>) and S texture (123<634>). A recrystallization microstructure containing numerous annealing twins together with a weak texture is observed in the 0.7mm-thick sheet after annealing at 700℃ for 10min. The yielding strength， tensile strength and final elongation are 293MPa， 433MPa and 33.4%， respectively， which are similar to those of the 0.7mm-thick annealed sheet produced by the conventional process.

Key words: strip casting, invar alloy, cold rolling, microstructure, texture, mechanical properties

CLC Number:

TG132.1

SONG Hong-yu， LIU Hai-tao， WANG Guo-dong. Study on Microstructure，Texture and Mechanical Properties of Strip Casting Invar Alloy[J]. Journal of Northeastern University Natural Science, 2020, 41(5): 723-728.

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