Browsing by Author "S, N."

Filter results by typing the first few letters
Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Effect of working parameters on the surface integrity in cryogenic diamond burnishing of 17-4 PH stainless steel with a novel diamond burnishing tool
    (2019) B, S.; S, N.; Chakradhar, D.
    The productivity of the components is adversely affected by the poor surface integrity characteristics as a consequence of the generation of high temperature in the burnishing zone. The abundant use of conventional lubricants causes environmental pollution and health problems. To overcome these issues, cryogenic cooling has been used across the world to reduce the temperature generated in the burnishing zone. It is well known that most of the accidents which involve aero engines have revealed that the reason for this may be due to the failure of the first stage of compressor blades. Hence aerospace material, 17-4 precipitation hardenable (PH) stainless steel can be used in aero engines to minimize the failure occurring due to foreign object damage. In the present study, the effect of cryogenic diamond burnishing on the surface integrity characteristics such as surface roughness, surface hardness, surface morphology, surface topography, subsurface microhardness, and residual stress of 17-4 pH stainless steel have been investigated with a novel diamond burnishing tool and also it has been related to dry and minimum quantity lubrication (MQL) environments. From the experimental results of diamond burnishing process, surface roughness was observed to be reduced by 33% 50%, 34% 51% and 25% 40% in the cryogenic cooling environment in contrast with MQL and dry environments. Similarly, the surface hardness improvement in a cryogenic cooling environment was found to be 5% 7%, 6% 10%, and 6% 9%, in comparison with MQL and dry environments respectively. 2019 The Society of Manufacturing Engineers
  • No Thumbnail Available
    Item
    Effect of working parameters on the surface integrity in cryogenic diamond burnishing of 17-4 PH stainless steel with a novel diamond burnishing tool
    (Elsevier Ltd, 2019) Sachin, B.; S, N.; Dupadu, D.
    The productivity of the components is adversely affected by the poor surface integrity characteristics as a consequence of the generation of high temperature in the burnishing zone. The abundant use of conventional lubricants causes environmental pollution and health problems. To overcome these issues, cryogenic cooling has been used across the world to reduce the temperature generated in the burnishing zone. It is well known that most of the accidents which involve aero engines have revealed that the reason for this may be due to the failure of the first stage of compressor blades. Hence aerospace material, 17-4 precipitation hardenable (PH) stainless steel can be used in aero engines to minimize the failure occurring due to foreign object damage. In the present study, the effect of cryogenic diamond burnishing on the surface integrity characteristics such as surface roughness, surface hardness, surface morphology, surface topography, subsurface microhardness, and residual stress of 17-4 pH stainless steel have been investigated with a novel diamond burnishing tool and also it has been related to dry and minimum quantity lubrication (MQL) environments. From the experimental results of diamond burnishing process, surface roughness was observed to be reduced by 33%–50%, 34%–51% and 25%–40% in the cryogenic cooling environment in contrast with MQL and dry environments. Similarly, the surface hardness improvement in a cryogenic cooling environment was found to be 5%–7%, 6%–10%, and 6%–9%, in comparison with MQL and dry environments respectively. © 2019 The Society of Manufacturing Engineers
  • No Thumbnail Available
    Item
    Influence of Microwave Power and EWAC-1004EN Filler Size on Characteristics of Inconel 625 and SS 304 Weldments Produced Using Microwave Irradiation Hybrid Joining System
    (Springer Nature, 2025) Kamble, D.L.; Sahu, R.K.; S, N.; Badiger, R.I.
    The present study focuses on welding of Inconel 625 (exotic) and SS 304 (general purpose) dissimilar alloys using the microwave irradiation hybrid joining system and subsequent characterization of the joint processed through microwave energy. The process parameters, namely microwave power (4.4 kW and 2.2 kW) and interfacial powder EWAC 1004 EN (average particle size: 75 µm and 25 µm) are employed. The individual influence of process parameters on weldment properties is studied. The joint specimens developed at 2.2 kW power show the enhancement of ultimate tensile strength (UTS), flexural strength (FS), and average microhardness by 33.44%, 71.42% and 31.25%, respectively, in contrast to their counterparts developed at 4.4 kW keeping particle size constant. Similarly, the UTS, FS and average microhardness of the specimens developed using EWAC-1004EN powder of average particle size (APS) 25 µm found to considerably increased by 76.07%, 32.06% and 55.55%, respectively, as compared to the joints developed using 75 µm APS with constant microwave power. This enhancement in the mechanical properties is attributed to the formation of different carbide and intermetallic phases such as NbC, Cr23C6, Cr2Ni3, Ni8Nb, and FeNi in the weld region which is evident from XRD. Furthermore, the fractured specimens obtained from tensile and flexural tests are examined using FESEM. It is observed that both ductile as well as brittle fracture occurred. This mixed fracture is particularly ascribed to the presence of secondary/ intermetallic phases in the fusion region. © King Fahd University of Petroleum & Minerals 2025.