Fracture and Structural Integrity e-ISSN 1971-8993 Open access
Damage mechanics Vol. 20, No. 76 (2026)

Influence of hybrid nano Al2O3–ZrO2 reinforcements on microstructure, fracture toughness and fractographic behaviour of Al6061 alloy

Author and affiliation details
  • Annapoorna Krishnappa Dept. of Mechanical Eng., RNS Institute of Technology, Visvesvaraya Technological University, India ORCID iD0000-0003-2543-4801
  • Shobha Ramesh Dept. of Industrial Eng. and Management, Ramaiah Institute of Technology, Bengaluru, Karnataka, India ORCID iD0000-0003-0210-3540
  • Rajanna Siddagangappa Dept. of Mechanical Eng., Government Engineering College, Mosale Hosahalli, Karnataka, India
  • Srimadhu Ashokkumar Trelleborg Sealing Solutions, Bengaluru, Karnataka, India
  • Manjunath Vatnalmath Assistant Professor, Dept. of Mechanical Eng., RNS Institute of Technology, Visvesvaraya Technological University, India, ORCID iD0000-0003-3138-9453
  • Virupaxi Auradi Corresponding author Dept. of Mechanical Engineering, Siddaganga Institute of Technology, Tumakuru-572103, Karnataka, India vsauradi@gmail.com
  • Madeva Nagaral Aircraft Research and Design Centre, Hindustan Aeronautics Limited, Bangalore-560037, Karnataka, India
DOI
10.3221/IGF-ESIS.76.14
Pages
223-237
Published
Licence
CC BY 4.0
Published inVol. 20, No. 76 (2026)Go to the issue

Abstract

A present study reveals the influence of nano Al2O3 and ZrO2 reinforcements on the fracture toughness of Hybrid Metal matrix Composites (HMMCs) made of Al6061 alloy. Composites are synthesized by varying weight fraction of alumina and Zirconia oxide using ultrasonic stir casing technique. Microstructural characterization of the synthesized composites for different weight fractions are carried out by using Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray Diffraction (XRD) which shows the uniform dissemination of the reinforced particulates, elemental composition and formation of phases. As per ASTM E399 fracture toughness was investigated which indicates the addition of nano sized reinforced particulates into the matrix alloy enhances the crack propagation resistance. Among the produced nano composites, Al6061-1 wt. % of Al2O3p+ ZrO2p shows maximum fracture toughness (47.39%) due to uniform dissemination of the nano reinforced particulates and load bearing capacity. The fractographic examination revealed a transition from ductile to mixed-mode fracture, with nanoparticles adequately disseminated to impede crack propagation and improve energy absorption. Meanwhile, further increase in the weight fraction of the reinforcing particulates leads to agglomeration there by reduces the fracture toughness. The results show that optimized nano hybrid reinforcement improves fracture toughness of Al6061 alloy and making it suitable for structural applications.

Keywords

Article history

  1. ReceivedUntil the next stage: 91 days
  2. Revision requestedUntil the next stage: 6 days
  3. RevisedUntil the next stage: 4 days
  4. AcceptedUntil the next stage: 1 day
  5. Published

How to cite

APA

Krishnappa, A., Ramesh, S., Siddagangappa, R., Ashokkumar, S., Vatnalmath, M., Auradi, V., & Nagaral, M. (2026). Influence of hybrid nano Al2O3–ZrO2 reinforcements on microstructure, fracture toughness and fractographic behaviour of Al6061 alloy. Fracture and Structural Integrity, 20(76), 223–237. https://doi.org/10.3221/IGF-ESIS.76.14

IEEE

A. Krishnappa et al., “Influence of hybrid nano Al2O3–ZrO2 reinforcements on microstructure, fracture toughness and fractographic behaviour of Al6061 alloy,” Fracture and Structural Integrity, vol. 20, no. 76, pp. 223–237, 2026, doi: 10.3221/IGF-ESIS.76.14.

MLA

Krishnappa, Annapoorna, et al. “Influence of hybrid nano Al2O3–ZrO2 reinforcements on microstructure, fracture toughness and fractographic behaviour of Al6061 alloy.” Fracture and Structural Integrity, vol. 20, no. 76, 2026, pp. 223–237. https://doi.org/10.3221/IGF-ESIS.76.14.

Chicago

Krishnappa, Annapoorna, Shobha Ramesh, Rajanna Siddagangappa, Srimadhu Ashokkumar, Manjunath Vatnalmath, Virupaxi Auradi, and Madeva Nagaral. 2026. “Influence of hybrid nano Al2O3–ZrO2 reinforcements on microstructure, fracture toughness and fractographic behaviour of Al6061 alloy.” Fracture and Structural Integrity 20 (76): 223–237. https://doi.org/10.3221/IGF-ESIS.76.14.

Harvard

Krishnappa, A., Ramesh, S., Siddagangappa, R., Ashokkumar, S., Vatnalmath, M., Auradi, V. and Nagaral, M. (2026) ‘Influence of hybrid nano Al2O3–ZrO2 reinforcements on microstructure, fracture toughness and fractographic behaviour of Al6061 alloy’, Fracture and Structural Integrity, 20(76), pp. 223–237. doi: 10.3221/IGF-ESIS.76.14.

Vancouver

Krishnappa A, Ramesh S, Siddagangappa R, Ashokkumar S, Vatnalmath M, Auradi V, et al. Influence of hybrid nano Al2O3–ZrO2 reinforcements on microstructure, fracture toughness and fractographic behaviour of Al6061 alloy. Fracture and Structural Integrity. 2026;20(76):223-237. doi:10.3221/IGF-ESIS.76.14

BibTeX

@article{krishnappa2026, author = {Krishnappa, Annapoorna and Ramesh, Shobha and Siddagangappa, Rajanna and Ashokkumar, Srimadhu and Vatnalmath, Manjunath and Auradi, Virupaxi and Nagaral, Madeva}, title = {Influence of hybrid nano Al2O3–ZrO2 reinforcements on microstructure, fracture toughness and fractographic behaviour of Al6061 alloy}, journal = {Fracture and Structural Integrity}, year = {2026}, volume = {20}, number = {76}, pages = {223--237}, doi = {10.3221/IGF-ESIS.76.14}, url = {https://doi.org/10.3221/IGF-ESIS.76.14}, issn = {1971-8993} }

RIS

TY - JOUR AU - Krishnappa, Annapoorna AU - Ramesh, Shobha AU - Siddagangappa, Rajanna AU - Ashokkumar, Srimadhu AU - Vatnalmath, Manjunath AU - Auradi, Virupaxi AU - Nagaral, Madeva TI - Influence of hybrid nano Al2O3–ZrO2 reinforcements on microstructure, fracture toughness and fractographic behaviour of Al6061 alloy JO - Fracture and Structural Integrity T2 - Fracture and Structural Integrity PY - 2026 DA - 2026/03/04 VL - 20 IS - 76 SP - 223 EP - 237 DO - 10.3221/IGF-ESIS.76.14 UR - https://doi.org/10.3221/IGF-ESIS.76.14 SN - 1971-8993 ER -

Licence

Creative Commons Attribution 4.0 International

May be shared and adapted, provided appropriate credit is given. Copyright © 2026 Annapoorna Krishnappa, Shobha Ramesh, Rajanna Siddagangappa, Srimadhu Ashokkumar, Manjunath Vatnalmath , Virupaxi Auradi, Madeva Nagaral.

Copyright 
Authors are allowed to retain both the copyright and the publishing rights of their articles without restrictions.  

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