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Jayamani, Jayaraj, Associate ProfessorORCID iD iconorcid.org/0000-0002-9436-4862
Publications (10 of 44) Show all publications
Maurya, H. S., Jayamani, J., Vikram, R. J., Juhani, K., Sergejev, F. & Prashanth, K. G. (2023). Additive manufacturing of TiC-based cermets: A detailed comparison with spark plasma sintered samples. Journal of Alloys and Compounds, 960, Article ID 170436.
Open this publication in new window or tab >>Additive manufacturing of TiC-based cermets: A detailed comparison with spark plasma sintered samples
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2023 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 960, article id 170436Article in journal (Refereed) Published
Abstract [en]

The present work is a comparative study on the TiC-430 L ferritic stainless steel (FSS) cermets manufactured via two powder metallurgical processes, namely, conventional spark plasma sintering (SPS) and metal additive manufacturing (AM) process (laser powder-bed fusion process (LPBF)/selective laser melting (SLM)). The rescanning strategy has been used to preheat and melt the powder bed with different laser parameters during the SLM process to suppress the presence of residual thermal stress leading to the fabrication of cermets without cracks. The as-fabricated SPS samples (95 %) show a relatively lower density than the SLM-built parts (~98 %). A study of their mechanical properties such as hardness, compressive strength, and fracture toughness was conducted and discussed in detail. Further, the corrosion behavior of the fabricated cermets parts was evaluated in 3.5 wt% NaCl. The SLM-prepared specimens reveal finer microstructures and better mechanical properties (compressive strength and fracture toughness) due to the presence of fine microstructure. Furthermore, the corrosion current density of TiC-430 L fss-based cermets fabricated by SLM is approximately 270 times lower than that of cermets parts fabricated by SPS, indicating excellent corrosion resistance. On the other hand, the hardness shows an opposite trend, where the SPS samples show the maximum hardness as compared to the SLM counterparts due to the presence of hard and coarse TiC particles along with some metallic carbides formed during the SPS process. The results reveal that AM processes not only can fabricate cermets with intricate shapes but can also fabricate them with improved mechanical and corrosion properties.

Keywords
TiC- 430 L fss-based Cermets, Selective laser melting, Spark plasma sintering, Microstructure, Mechanical properties, Corrosion resistance
National Category
Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:du-46111 (URN)10.1016/j.jallcom.2023.170436 (DOI)001124089700001 ()2-s2.0-85160511481 (Scopus ID)
Available from: 2023-06-01 Created: 2023-06-01 Last updated: 2024-01-02Bibliographically approved
Jayamani, J., Elo, R., Surreddi, K. B. & Olsson, M. (2023). Electrochemical and passivation behavior of a corrosion-resistant WC-Ni(W) cemented carbide in synthetic mine water. International journal of refractory metals & hard materials, 114, Article ID 106227.
Open this publication in new window or tab >>Electrochemical and passivation behavior of a corrosion-resistant WC-Ni(W) cemented carbide in synthetic mine water
2023 (English)In: International journal of refractory metals & hard materials, ISSN 0263-4368, Vol. 114, article id 106227Article in journal (Refereed) Published
Abstract [en]

Two different grades, WC-20 vol.% Ni and WC-20 vol.% Co cemented carbides, respectively were systematically investigated concerning their microstructure, binder composition, and corrosion behavior. SEM-EBSD analysis verified that both grades have similar WC grain sizes (0.9–1.1 μm). AES analysis confirmed that the binder phase of the respective grade is an alloy of Ni-W and Co-W and that the concentration of W in the Ni- and Co-binder is 21 and 10 at. %, respectively. In synthetic mine water (SMW), the EIS behavior of WC-Ni(W) at the open circuit potential (OCP) conditions was studied for different exposure periods (up to 120 h). The EIS data fitting estimates low capacitance and high charge transfer resistance (Rct) values, which indicate that the passive film formed on WC-Ni(W) is thin and exhibits high corrosion resistance. At the OCP and potentiostatic-passive conditions, SEM investigations confirm the uncorroded microstructure of the WC-Ni(W). The AR-XPS studies confirmed the formation of an extremely thin (0.25 nm) WO3 passive film is responsible for the high corrosion resistance of WC-Ni(W), at OCP conditions. However, above the transpassive potential, the microstructure instability of WC-Ni(W) was observed, i.e., corroded morphology of both WC grains and Ni(W) binder. The electrochemical parameters, Rct, corrosion current density, and charge density values, confirmed that the WC-Ni(W) is a far better alternative than the WC-Co(W) for application in SMW.

Keywords
Cemented carbides, Binder phases, EIS, Corrosion, Passivation, AR-XPS, AES
National Category
Materials Engineering
Identifiers
urn:nbn:se:du-45915 (URN)10.1016/j.ijrmhm.2023.106227 (DOI)001032173200001 ()2-s2.0-85153334592 (Scopus ID)
Available from: 2023-04-26 Created: 2023-04-26 Last updated: 2023-08-15Bibliographically approved
Maurya, H. S., Jayamani, J., Wang, Z., Juhani, K., Sergejev, F. & Prashanth, K. G. (2023). Investigation of the tribological behavior of the additively manufactured TiC-based cermets by scratch testing. Journal of Alloys and Compounds, 959, Article ID 170496.
Open this publication in new window or tab >>Investigation of the tribological behavior of the additively manufactured TiC-based cermets by scratch testing
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2023 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 959, article id 170496Article in journal (Refereed) Published
Abstract [en]

This study deals with the tribological behavior of the TiC-430 L SS cermets fabricated via an additive manufacturing process such as laser powder bed fusion/selective laser melting. A gradient microstructure (finer and coarser morphology) can be observed in the fabricated parts due to SLM's complex thermal history. Using Rockwell indenter, single and multiple passes scratch tests have been performed as a function of applied load to study the wear mechanism of the binder and matrix phase. A surface 3D profilometer was used to analyze the scratch track variation in terms of scratch width and depth. Scanning Electron microscopy (SEM) analysis was performed on the scratched cermet parts to study the wear mechanism and microstructural analysis. It has been observed that the scratch hardness increases with increasing load and the same decreases with increasing the number of passes. Similarly, the coefficient of friction increases with increasing load. Cermets with complex microstructural features exhibit high wear resistance under low loads and for higher loads, multiple passes can lead to tribolayer formation.

Keywords
TiC-based cermets, Selective laser melting, Wear, Tribo-layer, Coefficient of friction
National Category
Materials Engineering
Identifiers
urn:nbn:se:du-46066 (URN)10.1016/j.jallcom.2023.170496 (DOI)000999382100001 ()2-s2.0-85159610254 (Scopus ID)
Available from: 2023-05-19 Created: 2023-05-19 Last updated: 2023-07-31Bibliographically approved
Sokkalingam, R., Chao, Z., Sivaprasad, K., Muthupandi, V., Jayamani, J., Ramasamy, P., . . . Prashanth, K. G. (2022). Additive Manufacturing of CoCrFeMnNi High-Entropy Alloy/AISI 316L Stainless Steel Bimetallic Structures. Advanced Engineering Materials, Article ID 2200341.
Open this publication in new window or tab >>Additive Manufacturing of CoCrFeMnNi High-Entropy Alloy/AISI 316L Stainless Steel Bimetallic Structures
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2022 (English)In: Advanced Engineering Materials, ISSN 1438-1656, E-ISSN 1527-2648, article id 2200341Article in journal (Refereed) Published
Abstract [en]

CoCrFeMnNi high-entropy alloy (HEA)/AISI 316L stainless steel bimetals were additively fabricated using selective laser melting (SLM). The bimetal structure comprises three regions, i.e., CoCrFeMnNi-HEA, AISI 316L stainless steel, and an interface between CoCrFeMnNi-HEA, AISI 316L stainless steel. SLM processing results in the formation of columnar grains extending over many built layers epitaxially in a preferential growth direction. The Vickers microhardness ranges mainly between 250 and 275 HV0.5 in all three observed regions. In addition, only a marginal variation in tensile strength is observed between the CoCrFeMnNi-HEA, AISI 316L stainless steel, and the CoCrFeMnNi-HEA/AISI 316L stainless steel bimetal. The unique higher work hardening behavior of the CoCrFeMnNi-HEA prevents failure along the CoCrFeMnNi-HEA side in the bimetallic structure during plastic deformation. The CoCrFeMnNi-HEA shows higher pitting susceptibility than the AISI 316L stainless steel in the bimetallic structure due to its lower pitting potential. Further, the presence of pores and lack of fusion spots further decreases the pitting resistance of the CoCrFeMnNi-HEA. Hence, the bimetal is prone to more preferential corrosion attack along the CoCrFeMnNi-HEA side due to its anodic behavior and defects.

National Category
Materials Engineering
Identifiers
urn:nbn:se:du-42102 (URN)10.1002/adem.202200341 (DOI)000818836800001 ()2-s2.0-85133038808 (Scopus ID)
Available from: 2022-08-15 Created: 2022-08-15 Last updated: 2023-03-17Bibliographically approved
Singh, N., Ummethala, R., Surreddi, K. B., Jayamani, J., Sokkalingam, R., Rajput, M., . . . Prashanth, K. (2022). Effect of TiB2 addition on the mechanical and biological response of spark plasma sintered Ti6Al7Nb matrix composites. Journal of Alloys and Compounds, 924, 166502-166502, Article ID 166502.
Open this publication in new window or tab >>Effect of TiB2 addition on the mechanical and biological response of spark plasma sintered Ti6Al7Nb matrix composites
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2022 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 924, p. 166502-166502, article id 166502Article in journal (Refereed) Published
National Category
Materials Engineering
Identifiers
urn:nbn:se:du-42105 (URN)10.1016/j.jallcom.2022.166502 (DOI)000865014700003 ()2-s2.0-85135714650 (Scopus ID)
Available from: 2022-08-11 Created: 2022-08-11 Last updated: 2023-03-17Bibliographically approved
Jayamani, J. & Olsson, M. (2021). Effect of tribo-layer on the corrosion behavior of WC-Co and WC-Ni cemented carbides in synthetic mine water. International journal of refractory metals & hard materials, 100, Article ID 105621.
Open this publication in new window or tab >>Effect of tribo-layer on the corrosion behavior of WC-Co and WC-Ni cemented carbides in synthetic mine water
2021 (English)In: International journal of refractory metals & hard materials, ISSN 0263-4368, Vol. 100, article id 105621Article in journal (Refereed) Published
National Category
Materials Engineering
Identifiers
urn:nbn:se:du-37650 (URN)10.1016/j.ijrmhm.2021.105621 (DOI)000687835200003 ()2-s2.0-85109190167 (Scopus ID)
Available from: 2021-07-06 Created: 2021-07-06 Last updated: 2023-04-14Bibliographically approved
Ummethala, R., Jayamani, J., Karamched, P. S., Rathinavelu, S., Singh, N., Surreddi, K. B. & Prashanth, K. G. (2021). In Vitro Corrosion Behavior of Selective Laser Melted Ti-35Nb-7Zr-5Ta. Journal of materials engineering and performance (Print)
Open this publication in new window or tab >>In Vitro Corrosion Behavior of Selective Laser Melted Ti-35Nb-7Zr-5Ta
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2021 (English)In: Journal of materials engineering and performance (Print), ISSN 1059-9495, E-ISSN 1544-1024Article in journal (Refereed) Published
Abstract [en]

Ti-35Nb-7Zr-5Ta (TNZT) alloy has been fabricated by selective laser melting (SLM) at different build orientations with respect to the base plate and the resulting disparities in the grain shape, size, preferred orientations and lattice strains have been determined. Potentiodynamic polarization tests performed under in vitro conditions indicated that the specimens built at 45° orientation showed the highest polarization resistance (24.5 kΩ cm2) and lowest rate of corrosion (0.23 μA cm−2) compared to the specimens built at other orientations. The corrosion behaviors of the SLM specimens have been correlated with their microstructural features and further compared with that of its spark plasma sintered (SPS) counterpart and commercial alloys such as Ti6Al4V and Ti6Al7Nb. Electrochemical impedance spectroscopy and potentiostatic measurements have revealed that the passive film forming on the TNZT sample at 45° orientation is highly stable and more protective than that of the other samples. Auger electron spectroscopy has confirmed that both Ti and Nb participate actively in the passive film formation on the SLM TNZT alloy.

National Category
Materials Engineering
Identifiers
urn:nbn:se:du-37654 (URN)10.1007/s11665-021-05940-9 (DOI)000661413300005 ()2-s2.0-85107833159 (Scopus ID)
Available from: 2021-07-06 Created: 2021-07-06 Last updated: 2023-04-14Bibliographically approved
Poddar, C., Ningshen, S. & Jayamani, J. (2020). Corrosion assessment of Ni60 Nb30Ta10 metallic glass and its partially crystallized alloy in concentrated nitric acid environment. Journal of Alloys and Compounds, 813
Open this publication in new window or tab >>Corrosion assessment of Ni60 Nb30Ta10 metallic glass and its partially crystallized alloy in concentrated nitric acid environment
2020 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 813Article in journal (Refereed) Published
Abstract [en]

The corrosion resistance and passive film properties of Ni60Nb30Ta10 metallic glass and partially crystallized ribbon were investigated in 11.5 M nitric acid. The XRD study confirms the formation of nano-crystalline α-Ni in the amorphous matrix during crystallization at 650 °C under vacuum for 1 h. The electrochemical impedance spectroscopy, potentiodynamic polarization, and Mott-Schottky studies on the metallic glass exhibited higher corrosion resistance compared to the partially crystallized ribbon. XPS confirms the enrichment of Nb2O5 and Ta2O5 in the passive film of the glassy structure, while α-Ni is depleted in a partially crystallized alloy that affected the corrosion resistance.

Keywords
Metallic glasses, Semiconducting, Corrosion, EIS, SEM, XPS
National Category
Materials Engineering
Identifiers
urn:nbn:se:du-31428 (URN)10.1016/j.jallcom.2019.152172 (DOI)
Available from: 2019-12-20 Created: 2019-12-20 Last updated: 2019-12-20Bibliographically approved
Thirathipviwat, P., Song, G., Jayamani, J., Bednarcik, J., Wendrock, H., Gemming, T., . . . Han, J. (2019). A comparison study of dislocation density, recrystallization and grain growth among nickel, FeNiCo ternary alloy and FeNiCoCrMn high entropy alloy. Journal of Alloys and Compounds, 790, 266-273
Open this publication in new window or tab >>A comparison study of dislocation density, recrystallization and grain growth among nickel, FeNiCo ternary alloy and FeNiCoCrMn high entropy alloy
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2019 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 790, p. 266-273Article in journal (Refereed) Published
Abstract [en]

The microstructural evolutions in terms of dislocation density, annealing twin density as well as with respect to microstructural changes due to recrystallization and grain growth were investigated in pure Ni, equiatomic FeNiCo alloy, and FeNiCoCrMn high entropy alloy (HEA) during the thermomechanical process. All samples were single phase and showed a face-centered cubic (FCC) lattice structure. This was maintained during thermomechanical processing comprising of cold swaging by 85% reduction of cross-sectional area and subsequent annealing at 800 °C. The level of dislocation accumulation during cold swaging increased with the number of constituent elements. The FeNiCoCrMn HEA obtained the highest dislocation density, followed by the FeNiCo and Ni, respectively. After the annealing at 800 °C for 0.5 h, all samples achieved the large fraction of recrystallized grains with minor fraction of substructured grains and no deformed grain. The FeNiCoCrMn HEA obtained the smallest recrystallized grain size (∼5 μm) after the annealing at 800 °C for 0.5 h. This could be a result of the highest dislocation density generated during cold swaging prior to the annealing. The prolonged annealing at 800 °C for up to 24 h led to a grain growth for all the samples, however, at different growth rates. The FeNiCoCrMn HEA revealed the lowest rate of grain growth, but the microstructural changes during the annealing were not significantly different between the FeNiCo and Ni samples. Besides the effect of the number of constituent elements, the type and the combination of constituent elements have an effect on the microstructural evolution during the annealing.

Keywords
High entropy alloys, Dislocation density, Grain growth, EBSD, X-ray diffraction
National Category
Materials Engineering
Research subject
Research Profiles 2009-2020, Steel Forming and Surface Engineering
Identifiers
urn:nbn:se:du-29833 (URN)10.1016/j.jallcom.2019.03.052 (DOI)000464663600032 ()2-s2.0-85063051522 (Scopus ID)
Available from: 2019-04-01 Created: 2019-04-01 Last updated: 2021-11-12Bibliographically approved
Kamachi Mudali, U., Jayamani, J., Raman, R. S. & Raj, B. (2019). Corrosion: An Overview of Types, Mechanism, and Requisites of Evaluation. In: Raman Singh, Baldev Raj, U. Kamachi Mudali, Prabhakar Singh (Ed.), Non‐Destructive Evaluation of Corrosion and Corrosion‐assisted Cracking: . John Wiley & Sons
Open this publication in new window or tab >>Corrosion: An Overview of Types, Mechanism, and Requisites of Evaluation
2019 (English)In: Non‐Destructive Evaluation of Corrosion and Corrosion‐assisted Cracking / [ed] Raman Singh, Baldev Raj, U. Kamachi Mudali, Prabhakar Singh, John Wiley & Sons, 2019Chapter in book (Refereed)
Abstract [en]

Corrosion of metals and alloys in an aqueous environment is generally an electrochemical process that requires four essential components: an aqueous electrolyte, an anode, a cathode, and a current carrying pathway (i.e. circuit). In electrochemical corrosion, the anodic oxidation reaction should be compensated by the reduction reaction at cathode. The basis for the types of corrosion is their appearance and propagation mode. The eight well-known forms of corrosion are uniform or general corrosion, galvanic corrosion, pitting corrosion, crevice corrosion, intergranular corrosion, dealloying or selective leaching, erosion corrosion, and environmentally assisted cracking. Apart from these eight forms, the microbiologically influenced corrosion is also considered as one of the important corrosion forms. Nondestructive technique plays a vital role for damage assessment and life extension of the component as it is suitable in detection of the early stages of corrosion so that corrective measures can be taken before damage becomes severe.

Place, publisher, year, edition, pages
John Wiley & Sons, 2019
Keywords
crevice corrosion, environmentally assisted cracking, erosion corrosion, galvanic corrosion, general corrosion, intergranular corrosion, microbiologically influenced corrosion, nondestructive technique, pitting corrosion, selective leaching
National Category
Materials Engineering
Identifiers
urn:nbn:se:du-46290 (URN)10.1002/9781118987735.ch2 (DOI)9781118350058 (ISBN)9781118987735 (ISBN)
Available from: 2023-06-22 Created: 2023-06-22 Last updated: 2023-06-22Bibliographically approved
Projects
FEEDER-Karaktärisering av tillsatsmaterial för LMDp-process – reparationSMART-Sprickbildning i nerskalade Ti-testgeometrier för LMDp reparationer
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-9436-4862

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