Biography
Dr. Krishna Valleti is a senior scientist with over two decades of experience in thin film coatings and surface engineering, specializing in Physical Vapor Deposition (PVD) technologies such as Cathodic Arc (CA-PVD), Electron Beam (EB-PVD), and Magnetron Sputtering (DC, Pulsed, HiPIMS). He earned his Ph.D. in Physics (Thin Films) from IIT Madras, where his thesis focused on the development of rotating cylindrical magnetron cathodes and studies on tantalum-based hard coatings.
His research spans nanocomposite coatings, solar selective coatings for concentrated solar power (CSP) applications, and thin films for sensors and biomedical applications. Dr. Valleti has made significant contributions to advanced materials science, authoring 30+ peer-reviewed publications in leading international journals and presenting at major global conferences. His innovations have resulted in three granted patents, including technologies for corrosion-resistant coatings for fuel cell separators, solar selective multi-layer coatings, and improved cylindrical magnetron cathode designs.
Recognized for academic excellence and research impact, he qualified in CSIR-NET with fellowship, GATE, and JEST, and received the Best Poster Award at the Society of Vacuum Coaters (SVC) Tech Con, USA. He has successfully led and completed multiple nationally sponsored projects under initiatives such as DST’s Clean Energy Research Initiative and Solar Energy Research Initiative, focusing on high-performance coatings, hydrogen embrittlement prevention, and tungsten composites for plasma-facing components.
As a mentor and educator, Dr. Valleti has guided Ph.D. and M.Tech students, trained JRFs, SRFs, PDFs, and supervised numerous trainees, fostering talent in materials science and engineering. He actively contributes to the scientific community as a member of American Vacuum Society (AVS), Materials Research Society of India (MRSI), Indian Institute of Metals (IIM), and Society of Vacuum Coaters (SVC), and serves as a reviewer for top journals in surface engineering and materials science.
Currently, Dr. Valleti leads research at the Centre for Engineered Coatings (CEC), ARCI, Hyderabad, driving innovations in advanced coating technologies for strategic applications in defense, energy, and industrial sectors. His work continues to bridge fundamental research and industrial implementation, positioning him as a key contributor to India’s advanced materials ecosystem.
Research Areas of Interest
1. Deposition of metal, metal nitride and oxide coatings by Physical Vapor Deposition (PVD) for advanced applications (conventional and Nanocomposite coatings)
2. Solar selective coatings for solar thermal CSP applications (Nitride based functionally multi-layered coatings)
3. Thin films for sensor applications
4. Thin films for biomedical applications
Highest Qualification
List of Publications
“Machining of Ni-based superalloys using CAPVD coated carbide tools” N Tandekar, A Kumar, K Valleti, Materials Today Communications 39 (2024) 109101
“Indentation size effects in hardness of annealed NiB coatings” A Soni, A Kumaraswamy, B Praveen Kumar, N P Wasekar, K Valleti, MRS Communications, 1-8 (2024)
“Influence of substrate bias on machining performance of TiAlN-coated drill bits” Nitin Tandekar, Pooja Miryalkar, L. Rama Krishna, Krishna Valleti, Materials and Manufacturing Process 39 (2024) 518
“An assessment of machining performance of CAPVD-Coated carbide tools in face milling of Ti-6Al-4V” Aditya Kumar, Nitin Tandekar, A. Venu Gopal, Krishna Valleti, Ceramics International, 50 (9) (2024) 16639
“Efficacy of TiCrN/DLC coatings for service life enhancement of stamping dies” Krishna Valleti, Pooja Miryalkar, Rama Krishna L, Vacuum 217 (2023) 112534
“Cathodic arc deposition of nanocrystalline titanium nitride thin film on fluorine doped tin oxide coated glass substrate: Crystal structural, microstructural, mechanical, optical and electrical properties” Jayaraman Senthil Selvan, Rajeev R. Pillai, Ramasubramanian Kannan, B. Baskar, Krishna Valleti, J. Manonmani, Ceramics International 49 (2023) 37072
“An assessment of tool life in drilling of Inconel 718 using cathodic arc PVD coated carbide bits” Nitin Tandekar, Ambati Sandeep, Praveen Kumar, Pooja Miryalkar, Krishna Valleti, The International Journal of Advanced Manufacturing Technology 120 (2022) 4821
“Improving the abrasive wear resistance of biomass briquetting machine components using cathodic arc physical vapor deposition coatings: A comparative study” Pooja Miryalkar, Sekhar Chavitlo, Nitin Tandekar, and Krishna Valleti, Journal of Vacuum Science & Technology A 39 (2021) 063404
“The monolithic α, β crystal structural design of piezoelectric poly vinylidene fluoride (PVDF) polymer/fullerene-based sensor array for the measurement of lung pressure” N. Manikandan, Krishna Valleti, K. Karupasamy, M. Divagar, Senthil Subramaniam, Sensing and Bio-Sensing Research 32 (2021) 100418
“Low Friction Coefficient Nanocomposite CrAlSiN/Gradient-CrAlSiCN Coatings for High Speed/Dry Machining Applications” Puneet C, Krishna Valleti, A Venu Gopal, Journal of Manufacturing Science and Engineering 143 (2021) 081013-1
“Cr-(CrN/TiAlN)m-AlSiN-AlSiO open-air stable solar selective coating for concentrated solar thermal power applications” Krishna Valleti, Smita G. Rao , Pooja Miryalkar , A. Sandeep, D. Srinivasa Rao, Solar Energy Materials & Solar Cells 215 (2020) 110634
“Microstructure and Wear of Cathodic Arc Physical Vapour Deposited TiAlN, TiCrN and n-TiAlN/a-Si3N4 Films” Manish Roy, S. Saha, and K. Valleti, Defence Science Journal 70 (2020) 656-663
“Optical and mechanical properties of Sol-gel prepared Titania (TiO2)–Silica (SiO2) mixed thin films ‘as prepared at 300K’ without any post heat treatment” B. M. Pratima, Krishna Valleti and A. Subrahmanyam, Materials Research Express 6 (2019) 026407
“Effect of Pulsed Biasing on the Droplet Formation and the Properties of Cylindrical Cathodic Arc–Grown Erosion-Resistant TiN Coatings” Krishna Valleti, K. Sai Jyotheender and D. Srinivasa Rao, Tribology Transactions, Volume 62(1) (2019): 88
“CrAlSiN nanocomposite thin films for high-speed machining applications” Puneet C, Krishna Valleti, A. Venu Gopal & S. V. Joshi, Materials and Manufacturing Processes, Volume 33 Issue 4 (2018): 371
“Influence of surface preparation on the tool life of cathodic arc PVD coated twist drills” Puneet C, Krishna Valleti, A. Venu Gopal, Journal of Manufacturing Processes 27 (2017): 233
“Studies on cathodic arc PVD grown TiCrN based erosion resistant thin films” Krishna Valleti, Puneet C, Rama Krishna L, and Shrikant V. Joshi, Journal of Vacuum Science & Technology A 34, 041512 (2016)
“High temperature stable solar selective coatings by cathodic arc PVD for heat collecting elements” Krishna Valleti, D. Murali Krishna, P. Mohan Reddy, Shrikant V. Joshi, Solar Energy Materials and Solar Cells 145 (2016):447
“Effect of microstructure and phase constitution on mechanical properties of Ti1−xAlxN coatings” Sai Pramod Pemmasani, Krishna Valleti, Ravi C. Gundakaram, Koteswararao V. Rajulapati, Ramakrishna Mantripragada, Suresh Koppoju, Shrikant V. Joshi, Applied Surface Science 313 (2014): 936
“Functional multi-layer nitride coatings for high temperature solar selective applications” Krishna Valleti, D. Murali Krishna, S.V. Joshi, Solar Energy Materials and Solar cells 121 (2014): 14
“Characterization of multilayer nitride coatings by electron microscopy and modulus mapping” Sai Pramod Pemmasani, Koteswararao V. Rajulapati, M. Ramakrishna, Krishna Valleti, Ravi C. Gundakaram, Shrikant V. Joshi, Materials Characterization 81 (2013): 7
“Factors influencing properties of CrN thin films grown by cylindrical cathodic arc physical vapor deposition on HSS substrates” Krishna Valleti, C. Rejin, Shrikant V. Joshi, Material Science and Engineering A 545 (2012): 155
“Structure-property correlations in cathodic arc deposited TiAlN coatings” Sai Pramod Pemmasania, Krishna Valleti, M. Ramakrishna, K.V. Rajulapati, Ravi C. Gundakaram, S.V. Joshi, Material Science Forum 702-703 (2012)
“Influence of substrate temperature and bias voltage on properties of chromium nitride thin films deposited by cylindrical cathodic arc deposition” Krishna Valleti, A. Jyothirmayi, M. Ramakrishna and S. V. Joshi, Journal of Vacuum Science and Technology A 29 (2011): 051515
“Processing – Structure – Property relationships in electron beam physical vapor deposited yttria stabilized zirconia coatings” D. Srinivasa Rao, Krishna Valleti, S. V. Joshi, G. Ranga Janardhan, Journal of Vacuum science and Technology A 29 (2011): 031501-1
“Studies on hard TaN thin film deposition by R C-Mag technique” Krishna Valleti, Journal of Vacuum Science and Technology A 27 (2009): 626
“Studies on phase dependent mechanical properties of DC magnetron sputtered TaN thin films: Evaluation of super hardness in orthorhombic Ta4N phase”. Krishna Valleti, A. Subrahmanyam, Shrikant V. Joshi, A. R. Phani, M. Passacantando and S. Santucci. Journal of Physics D: Applied Physics 41 (2008): 045409
“Growth of nanocrystalline near α-phase Tantalum thin films at room temperature using cylindrical magnetron cathode”. Krishna Valleti, A. Subrahmanyam and Shrikant V. Joshi. Surface & Coatings Technology 202 (2008): 3325.
“The effect of arc suppression on the physical properties of Low temperature DC magnetron sputtered tantalum thin films”. A. Subrahmanyam, Krishna Valleti, Shrikant V. Joshi, and G. Sundararajan. Journal of Vacuum Science and Technology A 25 (2007): 378
“Pulsed DC magnetron sputtered tantalum nitride hard coatings for tribological applications”. Aditya Aryasomayajula, Krishna Valleti, Subrahmanyam Aryasomayajula, Deepak G. Bhat. Surface & Coatings Technology 201 (2006): 4401.
Conference Proceedings
“Cathodic Arc PVD grown thin films/coatings for strategic applications” International Conference on Advanced Materials and Processes for Defence Applications (ADMAT) September 23 – September 25 2019, Hyderabad, India.
“An endeavour to understand erosion failure mechanism in TiCrN coatings” 42nd ICMCTF Conference, April 20th – 24th 2015, San Diego, U.S.A.
“Influence of Composition and Architecture on Mechanical Properties of Cathodic Arc Deposited Ti-Al-N Coatings” 40th ICMCTF Conference, April 29th – May 3rd 2013, San Diego, U.S.A.
“Nanostructured Nitride Coatings for Improved Wear and Corrosion Resistance” International Conference on Nanoscience and Nanotechnology (ICONSAT 2012), Jan 21st -23rd 2012, Hyderabad, India
“Implementation of C-CAPVD grown refractory metal nitride coatings for solar thermal applications” International Conference on Nanoscience and Technology 2012, January 20 –January 23, Hyderabad, India.
“Studies on pulsed rotating cylindrical magnetron sputtered tantalum thin films” 50th Annual Society of Vacuum Coaters (SVC) Technical Conference, April 28- May 3, 2007, Louisville, Kentucky, USA. “Received Best Poster Award”
“Effect of grain size on mechanical properties of Pulsed DC magnetron sputtered Tantalum thin films” Eighth International Conference on Nanostructured Materials, August 20-25,
2006, IISc Bangalore, INDIA.
“Studies on Pulsed DC magnetron sputtered Tantalum thin films for hard coating applications: Effect of substrate temperature” 5th international surface engineering congress during May 15-17, 2006, Seattle, Washington, USA.
Patents
“Durable corrosion resistant coating for fuel cell separator and the process thereof” Sundararajan Ramakrishnan, Natarajan Rajalakshmi, Krishna Valleti, Indian Patent No.: 558766 granted on 27.01.2025.
“An improved solar selective multi-layer coating and a method of depositing the same” Indian Patent No: 303791, Grant date: 30/11/2018
“Improved cylindrical magnetron cathode and a process for depositing thin films on surfaces using the said cathode” Indian Patent No: 320582, Grant date: 16/09/2019.
Awards & Honours
1. Qualified in CSIR - NET with fellowship, GATE & JEST - 2003
2. Received Best Poster Award at the SVC 50th Anniversary Tech Con, Louisville, USA (2007) with a cash prize of $ 200.
Affiliation to Professional Societies
1. American Vacuum Society (AVS) - ID: 33833
2. Materials Research Society of India (MRSI) - No: LMB2370
3. The Indian Institute of Metals (IIM) - No: LM01-53933
4. Sensors Research Society - No: 219
5. Society of Vacuum Coaters (SVC)