Options
Kamaraj M
Loading...
Preferred name
Kamaraj M
Official Name
Kamaraj M
Alternative Name
Kamaraj, Muthusamy
Kamaraj, M.
Main Affiliation
Email
ORCID
Scopus Author ID
Google Scholar ID
7 results
Now showing 1 - 7 of 7
- PublicationEffect of Laser Surface Melting on Atmospheric Plasma Sprayed High-Entropy Alloy Coatings(01-01-2023)
;Kumar, Himanshu ;Manikandan, S. G.K.; Shiva, S.Laser surface melting (LSM) is the most helpful technique to improve the surface properties of the high-entropy alloy (HEA). LSM reduces the pores, voids, cracks, and other surface defects at the sample's surface. LSM utilized high-power fiber laser to partially or fully melt the surface to enhance the various properties such as wear, corrosion, and fatigue resistance without impacting the bulk material properties. LSM of HEA enhances the microhardness and wear properties by reducing the pores and surface defects. It facilitates flexibility such as control over laser spot diameter, penetration depth, mode of operation, and higher cooling rate, which increase its applicability in various applications such as automobile, medical, and aerospace. The relevance of LSM in wear-resistant applications is increasing among multiple sectors. The application domain of LSM ranges from cladding to repairing components. The LSM gained popularity over time due to its ability to improve the surface properties of specimens in a lower lead time. The HEA is a novel class of material used for wear and high-temperature applications due to its high configurational entropy and superior wear, oxidation, and corrosion resistance. Many researchers are working on the LSM of various HEAs to be applied in wear resistance applications. This chapter introduces the different types of laser-based surface modification techniques and their application in detail. This chapter also describes the effect of LSM on the microstructure and microhardness of atmospheric plasma sprayed HEA and compares it with the as-deposited alloy. This chapter will serve as a quick start for researchers to appreciate the improvement with laser-based surface modification techniques. - PublicationLaser surface modification of steel for slurry erosion resistance in power plants(01-03-2012)
;Shivamurthy, R. C.; ; ;Shariff, S. M.Padmanabham, G.This chapter discusses the microstructure and slurry erosion characteristics of laser surface alloyed coatings that are used to mitigate the erosion issues of 13Cr-4Ni martensitic stainless steel. The chapter first describes the present scenario of surface modification methods, such as conventional welding, surface hardening/nitriding, external coatings, etc., which are being utilized to minimize the silt erosion problems of components in hydropower plants. The chapter also explains newer coating methods, such as laser surface alloying. It then describes the usefulness towards erosion mitigation in hydropower plant applications of laser surface alloying of 13Cr-4Ni steels with commercial coating powders such as Colmonoy 88 and Stellite 6. Erosion performances of coatings and substrates are evaluated using a slurry jet erosion test-rig with various parameters, using commercial silica sand and river sand. An evaluation of the effect of boron carbide addition on the erosion performances of laser surface alloyed coatings is given. An attempt has also been made to correlate the quantitative results (erosion performances) with qualitative results (erosion mechanisms) by extensive studies of eroded samples using scanning electron microscopy. By the end of the chapter, a correlation between measured and predicted erosion rates has been established in power-law formulation. © 2013 Woodhead Publishing Limited All rights reserved. - PublicationWelding the inconel 718 superalloy: Reduction of micro-segregation and laves phases(01-01-2019)
;Manikandan, S. G.K. ;Sivakumar, D.Welding the Inconel 718 Superalloy: Reduction of Micro-segregation and Laves Phases explores the day-to-day welding business in Alloy 718 and presents solutions to avoid or minimize micro-segregation. It considers the limitations of changing from lab scale models to actual production models and presents new technologies with proven experimental background. Various case studies are presented within the text, as well as proposed solutions backed by experimental evidence. Items previewed in this edition include enhanced cooling rates in the GTA welding process with cryogenic cooling and enhanced dendrite refinement using modified pulse waveform. This work will be useful to researchers from the aerospace, space, power generation, nuclear, and chemical industries, as well as students interested in superalloys and welding. - PublicationSurface modified biochemical titanium alloys(01-12-2010)
;Vadiraj, AravindLoad bearing implants such as hip joints, knee joints and bone plates etc. are prone to failure from the conjoint effect of wear, fretting and corrosion from the movement of body. Modular junctions of hip implants consist of ball on a shaft which is under sliding conditions during body movements like walking etc. Fretting is experienced at ball and shaft contact. Fretting wear or fretting fatigue is a form of adhesive wear phenomenon wherein a small tangential oscillatory motion under certain contact pressure gradually erodes the surface and initiates crack within the contact leading to ultimate failure of the material under fatigue loading condition. Titanium alloys, Stainless steels and Co-Cr-Mo alloys are most commonly used for medical grade devices. Titanium alloys has high strength to weight ratio, superior biocompatibility and corrosion resistance compare to other materials. Fretting fatigue life of surface modified titanium alloys has improved compared to unmodified materials due to enhancement in surface properties and reduction in friction. © 2010 by Nova Science Publishers, Inc. All rights reserved. - PublicationFretting wear and fretting fatigue studies of surface modified biomedical titanium alloys(01-12-2010)
;Vadiraj, AravindLoad bearing implants such as hip joints, knee joints and bone plates etc. are prone to failure from the synergistic effect of fretting wear and fatigue during physical bodily movement. Fretting wear or fretting fatigue is a form of adhesive wear phenomenon wherein a small tangential oscillatory motion under high contact pressure gradually erodes the surface and initiates crack within the contact leading to ultimate failure of the material under fatigue loading condition. Modular junctions of hip implants consist of ball on a tapered shaft experiencing fretting wear during body movements. Titanium alloys, Stainless steels and Co-Cr-Mo alloys are the most commonly used alloys for medical grade devices. Titanium alloys has high strength to weight ratio, superior biocompatibility and corrosion resistance compare to other materials. Surface modified titanium alloys have better tribological properties. In this work, the substrate materials used are Ti-6Al-4V and Ti-6Al-7Nb. PVD TiN coating, plasma nitriding, nitrogen ion implantation, laser nitriding favors formation of TiN and Ti2N of different thickness according to the process. Thermal oxidation process favors formation of hard and brittle oxide layer. Fretting wear tests were conducted to study the quality of the coatings and modified layers. Laser nitriding and PVD TiN coating has shown better performance than other coatings due to high hardness of the layers. Friction coefficient for PVD TiN coating is around 0.2 throughout the test. Wear volume for PVD TiN coated and laser nitrided samples were almost 10 and 50 times lesser than other coatings respectively. Fretting fatigue life of surface modified titanium alloys has considerably improved compared to unmodified materials. Plasma nitrided pairs have shown the best performance over all the coatings. The average fretting fatigue lives of unmodified pairs were 15 to 18% of plasma nitrided pairs, 45 to 50% of the PVD TiN coated pairs and about 60% of ion implanted pairs. Fretting of unmodified alloy pairs have shown high friction and oxidation at the contact due to metallurgical compatibility of the pairs. Fretting of PVD TiN pairs have shown delamination and subsequent oxidation. The damage and friction generated within the contact is a complex interaction between third body particulates, oxide debris and ringer solution. Fretting fatigue life is more for plasma nitride pairs compared to all other modification processes. The damage of ion implanted pairs is similar to unmodified alloys with little improvement in fretting fatigue life. Laser nitrided pairs and thermally oxidation pairs have shown poor fretting fatigue life due to high case thickness and inhomogenities of the layers formed. Friction generated is low compared to al other process, but the specimens experienced premature failure at higher loads. © 2010 Nova Science Publishers, Inc. All rights reserved. - PublicationHigh Temperature Dry Sliding Wear Behaviour of Al-Si/Graphite Composites Processed by Stir Casting(20-04-2011)
;Rajaram, G. ;Kumaran, S. ;Srinivasa Rao, T.Aluminum alloy composites are extensively used for tribological applications due to excellent wear resistance especially during sliding under different operating conditions such as dry, wet and high temperature environments. In this present study, dry sliding wear behavior of aluminum silicon alloy reinforced with graphite (3 wt.%) was investigated by using Pin on Disc wear tester with different temperatures up to 350°C in air. The wear rate of alloy and composite was decreased with increasing temperature due to oxide and glazing layers formation. However, the wear behaviour of composites were superior than that of alloy for all temperature conditions due to formation of rich tribo film between sliding surfaces by smeared graphite particulates. The alloy could sustain only up to 300°C during sliding, but the composite could prolong till 350°C. The worn surfaces of alloy and composites were characterized by scanning electron microscope to understand the wear mechanism. - PublicationLaser surface modification of steel for slurry erosion resistance in power plants(01-01-2012)
;Shivamurthy, R. C.; ; ;Shariff, S. M.Padmanabham, G.This chapter discusses the microstructure and slurry erosion characteristics of laser surface alloyed coatings that are used to mitigate the erosion issues of 13Cr-4Ni martensitic stainless steel. The chapter first describes the present scenario of surface modification methods, such as conventional welding, surface hardening/nitriding, external coatings, etc., which are being utilized to minimize the silt erosion problems of components in hydropower plants. The chapter also explains newer coating methods, such as laser surface alloying. It then describes the usefulness towards erosion mitigation in hydropower plant applications of laser surface alloying of 13Cr-4Ni steels with commercial coating powders such as Colmonoy 88 and Stellite 6. Erosion performances of coatings and substrates are evaluated using a slurry jet erosion test-rig with various parameters, using commercial silica sand and river sand. An evaluation of the effect of boron carbide addition on the erosion performances of laser surface alloyed coatings is given. An attempt has also been made to correlate the quantitative results (erosion performances) with qualitative results (erosion mechanisms) by extensive studies of eroded samples using scanning electron microscopy. By the end of the chapter, a correlation between measured and predicted erosion rates has been established in power-law formulation.