International Journal of Surface Science and Engineering (5 papers in press)

Regular Issues

• APPLICATION OF GOV (FLOW PEENING) PROCESS TO IMPROVE SURFACE QUALITY OF Ti-6Al-4V OF AEROSPACE MATERIAL  
  by Murat Kalak, Burak Sahin, ?brahim GÖV, Abdurrahman Do?an, Kursad GOV 
  Abstract: Ti-6Al-4V is a difficult to cut material has wide applications due to its superior mechanical features. Non-traditional surface treatment methods namely abrasive flow machining and shot peening are applied to obtain desired surface quality. GOV (flow peening) process having advantages of surface quality and strength improvement (compressive residual stress generation) of AFM and shot peening respectively was developed. In this paper, the effects of the GOV process parameters (number of cycles, steel ball size, media ratio) on the material surfaces were investigated to evaluate surface roughness (Ra), material removal amount and white layer thickness. The surface roughness, Ra value was decreased from 2.17
  Keywords: Flow peening (GOV) process; Surface finishing; Abrasive flow machining; Aerospace materials; Ti-6Al-4V; White layer.
  DOI: 10.1504/IJSURFSE.2023.10054208
   
  
• Investigation of the Effect of NiCrAlY/Cr2O3/YSZ Plasma Coatings on Erosion Performance of MDN 420 Steel at High Temperature  
  by Madhu Sudana Reddy G, Durga Prasad C, Pradeep Patil, Gagan Shetty, Naresh Kakur, Ramesh M. R 
  Abstract: The purpose of the current study was to use an air jet erosion tester to examine the erosive behaviour of plasma sprayed coatings on MDN-420 that were composed of 70% NiCrAlY, 25% Cr2O3, and 5% YSZ. Microstructure and phase studies were performed. Measurements were made on the microhardness and adhesion strength. Al2O3 erodent was used in a solid particle erosion test with impact angles of 30
  Keywords: MDN-420 alloy; NiCrAlY/Cr2O3/YSZ; plasma spray; erosion; high temperature.
  DOI: 10.1504/IJSURFSE.2023.10054266
   
  
• Surface integrity and chip morphology in Ti-6Al-4V machining under CO2 cooling with Vortex Tube  
  by Khirod Mahapatro, Vamsi Krishna P 
  Abstract: Machining titanium alloys is a difficult job due to high heat generation and shorter tool life attributed to their inherent properties. In Ti-6Al-4V machining, the segmented type chips are formed with poor surface integrity, and tensile residual stresses are generated on the surface of machined components. The difficulties arising in titanium alloy machining can be minimised by removing the heat effectively. In the present work, vortex tube cooling system (VTCS) is used to supply the cold CO2 gas. Chip morphology, surface quality, tool wear, and surface residual stresses are analysed and compared to dry cutting. The experimental results revealed that VTCS reduced the width of segmented chips, reduced flank wear up to 48% relative to dry cutting. Crater wear zone width is reduced slightly and notch wear is almost eliminated. Chip segments and accumulated edge fragments are decreased on the machined surface, compressive surface residual stresses are developed.
  Keywords: vortex tube; CO2 gas cooling; chip morphology; surface morphology; tool wear; and surface residual stresses.
  DOI: 10.1504/IJSURFSE.2023.10054320
   
  
• Evaluation of Lubricant properties of bio-lubricant formulations developed from Neem Seed Oil  
  by Krishnaprasad S. Menon, Ambigai Rajasekaran 
  Abstract: The use of petroleum products as lubricants has already created a large number of environmental problems and this creates the importance of the search for environment-friendly vegetable oils. This study evaluates and compares the lubricant properties of neem seed oil with various proportions of stearic acid and low-density polyethylene (LDPE) separately as additives and compared with the mineral oil, SAE20W40. The bio-lubricant formulation of neem seed oil with 2% stearic acid reduced the wear scar diameter (WSD) of the base oil by 30%, and the coefficient of friction (COF) by 46.3%. At the same time, LDPE does not have a major role in varying the tribological property. The addition of LDPE had outstanding effects on improving the viscosity of neem seed oil whereas stearic acid did not improve the viscosity of the base oil considerably. The cold flow properties of the samples were evaluated using differential scanning calorimetry (DSC).
  Keywords: neem seed oil; additives; lubrication properties; wear; coefficient of friction; viscosity; bio-lubricant.
  DOI: 10.1504/IJSURFSE.2023.10054748
   
  
• Effect of environments on the tribological behavior of pure and graphene coated nickel against stainless steel counterpart  
  by Iram Zahra, Yong Sun, Zeeshan Anjum, Meysam N. Azadani, Ambreen Tajmal 
  Abstract: Friction and wear are a major cause of failure experienced by the mechanical components. Service life of these components can be improved by the application of different surface modifications and lubricating techniques. In this research work, tribological investigation of pure and graphene coated nickel specimens, in contact with stainless steel ball was conducted using pin-on-disc (PoD) tribometer test setup. Multilayered graphene coatings, approximately 20 nm in thickness, were applied using atmospheric pressure chemical vapor deposition (APCVD). Tests were conducted under similar loading conditions in four different environments: dry ambient, distilled water, saline water (3% NaCl) and mineral oil. Maximum coefficient of friction (COF), wear debris and wear track width were observed when pure nickel specimens were tested under dry ambient conditions. Graphene coating caused significant reduction in COF as well as in the width of wear scars. A minimum COF of 0.05 was achieved in graphene coated specimens under dry and mineral oil environments. Abrasive wear was the dominant phenomenon in case of pure nickel and stainless steel tribopair, while adhesive wear was observed in graphene coated and stainless steel tribopair. Microscopic analysis also revealed corrosive phenomenon in NaCl environment.
  Keywords: graphene; nickel; coating; tribological; friction; wear; microscopic analysis.
  DOI: 10.1504/IJSURFSE.2023.10054848