TY - JOUR

T1 - Observations of the occurrence and disappearance of peritectic couple growth performed under microgravity conditions

AU - Ludwig, Andreas

AU - Mogeritsch, Johann Peter

N1 - © 2023 The Authors

PY - 2023/10/4

Y1 - 2023/10/4

N2 - Peritectic couple growth (PCG) is an unusual growth form at which the peritectic and pro-peritectic solid phases solidify like a regular eutectic. To investigate the dynamics of PCG formation and growth, experiments with the transparent, organic peritectic alloy Tris(hydroxymethyl)aminomethane–Neopentylglycol are performed at the International Space Station. Fully planar and partly planar/cellular PCGs are found and analyzed. In any case, PCG starts with the formation of lateral bands from the peritectic phase that overgrow most of the pro-peritectic phase but not completely. During coupled growth, the remaining patches transform into rods and/or lamellae. Depending on the conditions, PCG either terminates by the disappearance of pro-peritectic rods or by transforming the rods into cells. The second mechanism goes hand in hand with the formation of a single-phase 2D layer at the top of a tilted interface. At low pulling velocities, planar pro-peritectic phase growth transforms into planar peritectic phase growth via PCG.

AB - Peritectic couple growth (PCG) is an unusual growth form at which the peritectic and pro-peritectic solid phases solidify like a regular eutectic. To investigate the dynamics of PCG formation and growth, experiments with the transparent, organic peritectic alloy Tris(hydroxymethyl)aminomethane–Neopentylglycol are performed at the International Space Station. Fully planar and partly planar/cellular PCGs are found and analyzed. In any case, PCG starts with the formation of lateral bands from the peritectic phase that overgrow most of the pro-peritectic phase but not completely. During coupled growth, the remaining patches transform into rods and/or lamellae. Depending on the conditions, PCG either terminates by the disappearance of pro-peritectic rods or by transforming the rods into cells. The second mechanism goes hand in hand with the formation of a single-phase 2D layer at the top of a tilted interface. At low pulling velocities, planar pro-peritectic phase growth transforms into planar peritectic phase growth via PCG.

KW - Peritectics

KW - Couple growth

KW - Transparent model alloy

KW - Microgravity

KW - Directional solidification

U2 - 10.1016/j.scriptamat.2023.115802

DO - 10.1016/j.scriptamat.2023.115802

M3 - Article

VL - 239.2024

JO - Scripta Materialia

JF - Scripta Materialia

SN - 1359-6462

IS - 15 January

M1 - 115802

ER -