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Evaluation of Horizontal and Vertical Constrained Rod Casting Mold on Hot Tearing Susceptibility of Al-Cu Alloys

Rajagukguk, Kardo (author), Suyitno, Suyitno (author), Saptoadi, Harwin (author), Kusumaningtyas, Indraswari (author), Arifvianto, Budi (author), Salim, Urip Agus (author), Mahardika, Muslim (author), Pujiyulianto, Eko (author), Katgerman, L. (author)

This research aims to evaluate horizontal and vertical constrained rod casting (CRC) molds on hot tearing susceptibility (HTS) of Al-xCu casting alloys with 2.2, 3.6, 7.5, and 12.5 percent Cu. The hot tears on the casting product were observed using a macroscopic approach. In addition, the hot tearing susceptibility of each casting product...

journal article 2024

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Effect of chemical composition on hot cracking susceptibility (HCS) using various hot cracking criteria

Pujiyulianto, E. (author), Rajagukguk, K. (author), Arifvianto, B. (author), Katgerman, L. (author), Paundra, F. (author), Yudistira, H. T. (author), Nurullah, F. P. (author), Muhyi, A. (author), Arif, M. F. (author)

The paper aims to evaluate the effect of chemical composition on the Hot Cracking Susceptibility (HCS) using mechanical and non-mechanical hot cracking criteria during solidification. The criteria were SKK as a mechanical criterion. Feurer, Clyne Davis, and Katgerman as non-mechanical criteria. The criteria were implemented at various...

journal article 2023

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Tailoring precipitation/properties and related mechanisms for a high-strength aluminum alloy plate via low-temperature retrogression and re-aging processes

Hou, L. G. (author), Yu, H. (author), Wang, Y. W. (author), You, L. (author), He, Z. B. (author), Wu, C. M. (author), Eskin, D. G. (author), Katgerman, L. (author), Zhuang, L. Z. (author), Zhang, J. S. (author)

The retrogression and re-aging (RRA) processes, aimed mainly at tailoring intergranular precipitates, could significantly improve the corrosion resistance (i.e., stress corrosion cracking resistance) without considerably decreasing the strength, which signifies that an efficient control of the size, distribution and evolution of intergranular...

journal article 2022

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Modelling of defects in aluminium cast products

Jolly, Mark (author), Katgerman, L. (author)

Over the last 4 decades, remarkable progress has been made in the modelling of casting processes. The development of casting models is well reflected in the proceedings of the 15 Modelling of Casting, Welding and Advanced Solidification Processes (MCWASP) conferences that have been held since 1980. Computer simulations have enabled a better...

journal article 2022

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Tuning homogenization of high-strength aluminum alloys through thermodynamic alloying approach

Wang, Yawen (author), Hou, Longgang (author), Su, Hui (author), Tian, Qingkun (author), Yu, Kangcai (author), Eskin, Dmitry (author), Katgerman, L. (author), Zhuang, Linzhong (author)

The alloy design and homogenization processes are intimately associated with the microstructure, phase composition and performance for Al-Zn-Mg-Cu alloys. The microstructures and phase composition of a series of Al-Zn-Mg-Cu alloys before and after the homogenization treatments were investigated along with thermodynamic calculation to...

journal article 2022

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Semi-solid Constitutive Parameters and Failure Behavior of a Cast AA7050 Alloy

Sosro Subroto, T.A. (author), Eskin, Dmitry G. (author), Miroux, A.G. (author), Ellingsen, Kjerstin (author), M’Hamdi, Mohammed (author), Katgerman, L. (author)

AA7050 is an aluminum alloy with superior mechanical properties; however, it is prone to hot tearing (HT) during its production via direct-chill casting. This study focuses on extracting constitutive parameters of the alloy thermomechanical behavior in semi-solid state as well as gaining insight in its failure behavior. Tensile tests were...

journal article 2021

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Recent advances in hot tearing during casting of aluminium alloys

Li, Yue (author), Li, Hongxiang (author), Katgerman, L. (author), Du, Qiang (author), Zhang, Jishan (author), Zhuang, Linzhong (author)

Hot tearing is one of the most severe and irreversible casting defects for many metallic materials. In 2004, Eskin et al. published a review paper in which the development of hot tearing of aluminium alloys was evaluated (Eskin and Suyitno, 2004). Sixteen years have passed and this domain has undergone considerable development. Nevertheless,...

review 2021

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Effect of Main Elements (Zn, Mg, and Cu) on Hot Tearing Susceptibility During Direct-Chill Casting of 7xxx Aluminum Alloys

Li, Y. (author), Zhang, Z. R. (author), Zhao, Z. Y. (author), Li, H. X. (author), Katgerman, L. (author), Zhang, J. S. (author), Zhuang, L. Z. (author)

New 7xxx aluminum alloys with high alloying contents are being designed, which could induce serious hot tearing defects during direct-chill (DC) casting. Among all factors affecting hot tearing of 7xxx alloys, undoubtedly alloying elements play a significant role. In this study, the effect of main alloying elements (Zn, Mg, and Cu) on hot...

journal article 2019

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Influence of ultrasonic melt treatment on the formation of primary intermetallics and related grain refinement in aluminum alloys

Zhang, L. (author), Eskin, D.G. (author), Katgerman, L. (author)

Ultrasonic melt treatment (UST) is known to induce grain refining in aluminum alloys. Previous studies have clearly shown that in Al–Zr–Ti alloys, the primary Al3Zr intermetallics were dramatically refined by cavitation-assisted fragmentation, and a good refinement effect was achieved. In this article, Al–Ti, Al–Ti–Zr alloys, and some commercial...

journal article 2011

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Cold cracking in DC-cast high strength aluminum alloy ingots: An intrinsic problem intensified by casting process parameters

Lalpoor, M. (author), Eskin, D.G. (author), Ruvalcaba, D. (author), Fjaer, H.G. (author), Ten Cate, A. (author), Ontijt, N. (author), Katgerman, L. (author)

For almost half a century the catastrophic failure of direct chill (DC) cast high strength aluminum alloys has been challenging the production of sound ingots. To overcome this problem, a criterion is required that can assist the researchers in predicting the critical conditions which facilitate the catastrophic failure of the ingots. This could...

journal article 2011

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Investigation of fracture behavior of high strength aluminum alloys in the as-cast condition

Lalpoor, M. (author), Eskin, D.G. (author), Katgerman, L. (author)

conference paper 2010

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Constitutive parameters, mechanical properties and failure mechanism in DC-cast AA7050 billets

Lalpoor, M. (author), Eskin, D.G. (author), Katgerman, L. (author)

conference paper 2010

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Numerical simulation of residual thermal stresses in AA7050 alloy during DC-casting using ALSIM5

Lalpoor, M. (author), Eskin, D.G. (author), Katgerman, L. (author)

Non-homogenous cooling rates and solidification conditions during DC-casting of high strength aluminum alloys result in the formation and accumulation of residual thermal stresses with different signs and magnitudes in different locations of the billet. Rapid propagation of microcracks in the presence of thermal stresses can lead to catastrophic...

conference paper 2010

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Cold cracking development in AA7050 DC-cast billets under various casting conditions

Lalpoor, M. (author), Eskin, D.G. (author), Katgerman, L. (author)

journal article 2010

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Application of a criterion for cold cracking to casting high strength aluminum alloys

Lalpoor, M. (author), Eskin, D.G. (author), Fjaer, H.G. (author), Ten Cate, A. (author), Ontijt, N. (author), Katgerman, L. (author)

Direct chill (DC) casting of high strength 7xxx series aluminium alloys is difficult mainly due to solidification cracking (hot cracks) and solid state cracking (cold cracks). Poor thermal properties along with extreme brittleness in the as-cast condition make DC-casting of such alloys a challenging process. Therefore, a criterion that can...

conference paper 2010

document

On the development of a cold cracking criterion for DC-casting of high strength aluminum alloys

Lalpoor, M. (author), Eskin, D.G. (author), Katgerman, L. (author)

conference paper 2010

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Cold-Cracking Assessment in AA7050 Billets during Direct-Chill Casting by Thermomechanical Simulation of Residual Thermal Stresses and Application of Fracture Mechanics

Lalpoor, M. (author), Eskin, D.G. (author), Katgerman, L. (author)

Thermally induced strains and stresses developed during direct-chill (DC) semicontinuous casting of high strength aluminum alloys can result in formation of micro-cracks in different locations of the billet. Rapid propagation of such micro-cracks in tensile thermal stress fields can lead to catastrophic failure of ingots in the solid state...

journal article 2009

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Integrated Approach for Prediction of Hot Tearing

Kool, W.H. (author), Katgerman, L. (author)

Shrinkage, imposed strain rate, and (lack of) feeding are considered the main factors that determine cavity formation or the formation of hot tears. A hot-tearing model is proposed that will combine a macroscopic description of the casting process and a microscopic model. The micromodel predicts whether porosity will form or a hot tear will...

journal article 2009

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In-Situ Analysis of Coarsening during Directional Solidification Experiments in High-Solute Aluminum Alloys

Ruvalcaba, D. (author), Mathiesen, R.H. (author), Eskin, D.G. (author), Arnberg, L. (author), Katgerman, L. (author)

Coarsening within the mushy zone during continuous directional solidification experiments was studied on an Al-30 wt pct Cu alloy. High brilliance synchrotron X-radiation microscopy allowed images to be taken in-situ during solidification. Transient conditions were present during directional solidification. Under these conditions, solute-rich...

journal article 2009

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Strain-dependent constitutive analysis of three wrought Mg–Al–Zn alloys

Slooff, F.A. (author), Zhou, J. (author), Duszczyk, J. (author), Katgerman, L. (author)

The commonly used hyperbolic sine constitutive equation for metal forming at elevated temperatures, with no strain incorporated, is in principle applicable only to deformation in the steady state. However, the actual deformation processes applied to magnesium alloys are mostly in the non-steady state. In the present research, the results of hot...

journal article 2008