Sandra N Gajevic

Dr. Sandra N Gajevic

Faculty of Engineering University of Kragujevac, Kragujevac, Serbia
orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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29 November 2024 in Lubricants
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Journal Article
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sachin kumar sharmasachin kumar sharma
sachin kumar sharma
Sandra N GajevicSandra N Gajevic
Sandra N Gajevic
LSLokesh Sharma
Lokesh Sharma
RPReshab Pradhan
Reshab Pradhan
Yogesh SharmaYogesh Sharma
Yogesh Sharma
Blaza StojanovićBlaza Stojanović
Blaza Stojanović
Manufacturing sectors, including automotive, aerospace, military, and aviation, are paying close attention to the increasing need for composite materials with better characteristics. Composite materials are significantly used in industry owing to their high-quality, low-cost materials with outstanding characteristics and low weight. Hence, aluminum-based materials are preferred over other traditional materials owing to their low cost, great wear resistance, and excellent strength-to-weight ratio. However, the mechanical characteristics and wear behavior of the Al-based materials can be further improved by using suitable reinforcing agents. The various reinforcing agents, including whiskers, particulates, continuous fibers, and discontinuous fibers, are widely used owing to enhanced tribological and mechanical behavior comparable to bare Al alloy. Further, the advancement in the overall characteristics of the composite material can be obtained by optimizing the process parameters of the processing approach and the amount and types of reinforcement. Amongst the various available techniques, stir casting is the most suitable technique for the manufacturing of composite material. The amount of reinforcement controls the porosity (%) of the composite, while the types of reinforcement identify the compatibility with Al alloy through improvement in the overall characteristics of the composites. Fly ash, SiC, TiC, Al2O3, TiO2, B4C, etc. are the most commonly used reinforcing agents in AMMCs (aluminum metal matrix composites). The current research emphasizes how different forms of reinforcement affect AMMCs and evaluates reinforcement influence on the mechanical and tribo characteristics of composite material.

9 August 2025 in Polymers
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Milan BukvicMilan Bukvic
Milan Bukvic
Saša T. MilojevićSaša T. Milojević
Saša T. Milojević
Sandra N GajevicSandra N Gajevic
Sandra N Gajevic
MĐMomčilo Đorđević
Momčilo Đorđević
Blaza StojanovićBlaza Stojanović
Blaza Stojanović
Composite materials have been increasingly used in various branches of industry, transport, construction, and medicine—as well as in other sectors of the economy and science—in recent decades. A significant advancement in the improvement of composite material characteristics has been achieved through the use of nanoparticles, which substantially enhance the properties of the base material, whether it is the matrix or the reinforcing phase in hybrid composites. The broad application of polymers and polymer composites in many areas of engineering has had a significant impact on reducing friction and wear, improving the thermal characteristics of individual components and entire technical systems, enhancing electrical conductivity, reducing the specific weight of components, lowering noise and vibration levels, and ultimately decreasing fuel consumption, production costs, and the costs of operation and maintenance of technical systems. This paper explores the potential applications of polymer composites in various assemblies and components of conventional vehicles, as well as in hybrid and electric vehicles. Furthermore, their use in medicine and the defense industry is examined—fields in which some authors believe composites were first pioneered. Finally, aviation represents an indispensable domain for the application of such materials, presenting unique exploitation boundary conditions, including dynamic environmental changes such as variations in temperature, pressure, velocity, and direction, as well as the need for high levels of protection. Future research can be unequivocally focused on the structural and technological advancement of polymer composites, specifically through optimization aimed at reducing waste and lowering production costs.

10 May 2024 in Lubricants
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Sandra N GajevicSandra N Gajevic
Sandra N Gajevic
AMAna Marković
Ana Marković
Saša T. MilojevićSaša T. Milojević
Saša T. Milojević
Aleksandar AšonjaAleksandar Ašonja
Aleksandar Ašonja
LILozica Ivanovic
Lozica Ivanovic
Blaza StojanovićBlaza Stojanović
Blaza Stojanović
In this study, a multi-objective optimization regarding the tribological characteristics of the hybrid composite with a base material of aluminum alloy A356 as a constituent, reinforced with a 10 wt.% of silicon carbide (SiC), size 39 µm, and 1, 3, and 5 wt.% graphite (Gr), size 35 µm, was performed using the Taguchi method, gray relational analysis (GRA), and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) decision-making methods. Tribological tests were carried out on a “block on disc” type tribometer with lubrication. Load, sliding speed, and graphite mass concentration were analyzed as input parameters. As output parameters, wear rate and coefficient of friction were calculated. An analysis of variance (ANOVA) was conducted to identify all parameters that have a significant influence on the output multi-response. It was found that the normal load has the highest influence of 41.86%, followed by sliding speed at 32.48% and graphite addition at 18.47%, on the tribological characteristics of composites. Multi-objective optimization determined that the minimal wear rate and coefficient of friction are obtained when the load is 40 N, the sliding speed is 1 m/s, and the composite contains 3 wt.% Gr. The optimal combination of parameters achieved by GRA was also confirmed by the TOPSIS method, which indicates that both methods can be used with high reliability to optimize the tribological characteristics. The analysis of worn surfaces using scanning electron microscopy revealed adhesive and delamination wear as dominant mechanisms.

23 October 2024 in Materials
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sachin kumar sharmasachin kumar sharma
sachin kumar sharma
Sandra N GajevicSandra N Gajevic
Sandra N Gajevic
LSLokesh Sharma
Lokesh Sharma
RPReshab Pradhan
Reshab Pradhan
Slavica MiladinovicSlavica Miladinovic
Slavica Miladinovic
Blaza StojanovićBlaza Stojanović
Blaza Stojanović
Magnesium (Mg) has attracted considerable attention as a biodegradable material for medical implants owing to its excellent biocompatibility, mitigating long-term toxicity and stress shielding. Nevertheless, challenges arise from its rapid degradation and low corrosion resistance under physiological conditions. To overcome these challenges, titanium (biocompatibility and corrosion resistance) has been integrated into Mg. The incorporation of titanium significantly improves mechanical and corrosion resistance properties, thereby enhancing performance in biological settings. Mg–Ti alloys are produced through mechanical alloying and spark plasma sintering (SPS). The SPS technique transforms powder mixtures into bulk materials while preserving structural integrity, resulting in enhanced corrosion resistance, particularly Mg80-Ti20 alloy in simulated body fluids. Moreover, Mg–Ti alloy revealed no more toxicity when assessed on pre-osteoblastic cells. Furthermore, the ability of Mg–Ti-based alloy to create composites with polymers such as PLGA (polylactic-co-glycolic acid) widen their biomedical applications by regulating degradation and ensuring pH stability. These alloys promote temporary orthopaedic implants, offering initial load-bearing capacity during the healing process of fractures without requiring a second surgery for removal. To address scalability constraints, further research is necessary to investigate additional consolidation methods beyond SPS. It is essential to evaluate the relationship between corrosion and mechanical loading to confirm their adequacy in physiological environments. This review article highlights the importance of mechanical characterization and corrosion evaluation of Mg–Ti alloys, reinforcing their applicability in fracture fixation and various biomedical implants.

25 January 2026 in Polymers
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Journal Article
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sachin kumar sharmasachin kumar sharma
sachin kumar sharma
LSLokesh Sharma
Lokesh Sharma
RPReshab Pradhan
Reshab Pradhan
Yogesh SharmaYogesh Sharma
Yogesh Sharma
MSMohit Sharma
Mohit Sharma
Blaza StojanovićBlaza Stojanović
Blaza Stojanović
Polymer composites reinforced with nanofillers, synthetic fibers, and inorganic fillers have progressed rapidly, yet recent advances remain fragmented across filler-specific studies and often lack unified mechanistic interpretation. This review addresses this gap by presenting an interphase-centric, mechanism-driven framework linking processing routes, dispersion and functionalization requirements, interphase formation, and the resulting structure–property relationships. Representative quantitative datasets and mechanistic schematics are integrated to rationalize nonlinear mechanical reinforcement, percolation-controlled electrical/thermal transport, and thermal stabilization and barrier effects across major filler families. The review highlights how reinforcement efficiency is governed primarily by interfacial adhesion, filler connectivity, and processing-induced microstructural evolution rather than filler loading alone. Key challenges limiting scalability are critically discussed, including dispersion reproducibility, viscosity and processability constraints, interphase durability, and recycling compatibility. Finally, mechanism-based design rules and future outlook directions are provided to guide the development of high-performance, multifunctional, and sustainability-oriented polymer composite systems.

1 January 2024 in Advanced Engineering Letters
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Journal Article
Open access
JKJovana Krstić
Jovana Krstić
JJJelena Jovanović
Jelena Jovanović
Sandra N GajevicSandra N Gajevic
Sandra N Gajevic
Slavica MiladinovicSlavica Miladinovic
Slavica Miladinovic
Nikolaos VaxevanidisNikolaos Vaxevanidis
Nikolaos Vaxevanidis
Blaza StojanovićBlaza Stojanović
Blaza Stojanović
Nanocomposites nowadays, have the tendency to replace conventional composite materials in many commercial products. These composites find application in a diverse range of fields, including computer components, data storage systems, various membranes and filters, as well as advanced materials in the automotive and aerospace industries. They are available in different forms and from various manufacturers, providing a wide selection. Although they may be more expensive, compared to conventional materials, the ability to customize the properties of nanocomposites to the specific needs of end-users makes them highly attractive and innovative. International scientific bodies, including International Standards Organization (ISO), are actively working on formulating standards to regulate the safe use, disposal and recycling of nanowaste. The importance of standardization will grow with the expansion of the market for metal matrix nanocomposites. The aim of this paper is to review the existing research on metal matrix nanocomposites and their application to achieve significant improvements in the chemical, aerospace, automotive and other industries.