TY - JOUR

T1 - Creep strain recovery of an in situ spinel-forming refractory castable under loading/unloading compressive creep conditions

AU - Akbari, Behnam

AU - Gruber, Dietmar

AU - Jin, Shengli

AU - Harmuth, Harald

N1 - Funding Information: The authors gratefully acknowledge the financial support under the scope of the COMET program within the K2 Center “ Integrated Computational Material, Process and Product Engineering (IC-MPPE) " (Project No 859480). This program is supported by the Austrian Federal Ministries for Transport, Innovation and Technology (BMVIT) and for Digital and Economic Affairs (BMDW) , represented by the Austrian research funding association (FFG) , and the federal states of Styria, Upper Austria and Tyrol. Publisher Copyright: © 2023 The Authors

PY - 2023/5/17

Y1 - 2023/5/17

N2 - Creep strain recovery after unloading has been well studied for metals and certain ceramic composites; however, it has not yet been investigated for ordinary ceramic refractories applied in industrial furnaces. The present study explores the question whether creep strain recovery can be observed in ordinary ceramic refractories to justify its consideration in the design of such refractories and refractory linings. To this end, the dependence of creep strain recovery on different loading conditions was investigated for a high-alumina in situ spinel-forming castable, commonly used as refractory lining of steel ladles in secondary steel metallurgy. Several loading/unloading compressive creep tests were performed at 1300 °C for different loading histories. Creep strain recovery was observed to occur and it was significantly affected by the holding time and degree of unloading. A longer holding time for the loading period was found to increase the internal stress, which is the driving force for creep strain recovery. In addition, the findings indicate that a higher excess of internal stress over external stress after unloading induces higher strain recovery.

AB - Creep strain recovery after unloading has been well studied for metals and certain ceramic composites; however, it has not yet been investigated for ordinary ceramic refractories applied in industrial furnaces. The present study explores the question whether creep strain recovery can be observed in ordinary ceramic refractories to justify its consideration in the design of such refractories and refractory linings. To this end, the dependence of creep strain recovery on different loading conditions was investigated for a high-alumina in situ spinel-forming castable, commonly used as refractory lining of steel ladles in secondary steel metallurgy. Several loading/unloading compressive creep tests were performed at 1300 °C for different loading histories. Creep strain recovery was observed to occur and it was significantly affected by the holding time and degree of unloading. A longer holding time for the loading period was found to increase the internal stress, which is the driving force for creep strain recovery. In addition, the findings indicate that a higher excess of internal stress over external stress after unloading induces higher strain recovery.

KW - Creep strain recovery

KW - In situ spinel-forming castable

KW - Internal stress

KW - Refractory

UR - http://www.scopus.com/inward/record.url?scp=85159895257&partnerID=8YFLogxK

U2 - 10.1016/j.ceramint.2023.05.055

DO - 10.1016/j.ceramint.2023.05.055

M3 - Article

AN - SCOPUS:85159895257

VL - 49.2023

SP - 25225

EP - 25231

JO - Ceramics International

JF - Ceramics International

SN - 0272-8842

IS - 15

ER -