International Journal of Nanomanufacturing (5 papers in press)

Regular Issues

• Tool Wear Mechanism of Micro-milling Inconel 718 Thin Wall  
  by Xiaohong Lu, Yihan Luan, Kun Yang, Feixiang Ruan, Pengrong Hou, Ning Zhao 
  Abstract: Tool wear makes it difficult to obtain high-quality tiny thin wall parts during micro-milling Inconel 718 process. In this paper, tool wear mechanism of coated cemented carbide micro-milling tool is studied based on Inconel 718 thin wall micro-milling experiments. The wear, damage morphology and failure mechanism of the rake face of the circumferential edge and the flank face of the circumferential edge of the micro-milling tool are studied. It is found that the main failure mode of micro-milling tool is the damage of micro-milling tool circumferential edge and coating shedding; the main cause of tool wear is the combination of adhesive wear, diffusion wear and oxidation wear during micro-milling Inconel 718 thin wall parts,. The research provides reference for reducing the tool wear, extending the service life of cutter, and achieving high-quality thin wall parts during micro-milling Inconel 718 process.
  Keywords: Micro-milling; tool wear; Inconel 718; thin wall.
  
  
• Experimental investigations on micro-end-milling of hardened die steel: effects of high-speed and high-efficiency side cutting  
  by Haruki Kino, Takumi Imada, Keiji Ogawa, Heisaburo Nakagawa, Hitomi Kojima 
  Abstract: The need for micro-end-milling technology is increasing in recent years as industrial parts become finer and more precise. For example, this trend is evident in the medical, optical, and electronic components fields. However, it seems to be difficult to achieve high-precision and high-efficiency in micro-end-milling. The reason for this is that small-diameter endmills have small rigidity and are easily deformed during machining, and therefore the depth of cut has to be set small. Hence, the authors have analysed the processing phenomenon in detail and the mechanism has been elucidated in order to solve these problems. In particular, the present paper discusses the effects of using a high-speed air-turbine spindle with rolling bearing to perform high-speed cutting. The cutting force, surface roughness, machining accuracy, and changes in tool wear were investigated in detail when hardened die steel was side-cut at high-speed. As a result, it was clarified that high-speed cutting can suppress the dimensional accuracy and shape error, and that high-efficiency machining can be achieved. It is not easy to perform theoretical analysis and numerical simulation in the machining analysis of micro end mills. Due to the small diameter of the tool and the extremely small depth of cut, the accuracy of the analysis becomes a problem and the discrepancy with the actual cutting phenomenon becomes large. Furthermore, the analysis becomes more difficult when the cutting speed is increased and the machining time is extremely short. In this study, experimental machining was first carried out, and sufficient useful knowledge was obtained. In the future, analytical efforts will also be conducted.
  Keywords: end mill; micro-end-milling; high-speed cutting; side cutting; hardened die steel; surface roughness; tool wear; cutting force; accuracy; tool life.
  
  
• Impact of substrate temperatures on active layer depositions of organic thin-film photovoltaic cells by electrospray  
  by Yoshiyuki Seike, Daiki Tangiku, Tatsuo Mori 
  Abstract: This study describes the relationship between the surface states of active layers and organic thin-film photovoltaic (OPV) cell properties when the active layer of an OPV cell is deposited through electrospray (ES). The mixture of poly(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-Phenyl C61 butyric acid methyl ester (PC61BM) was deposited via ES. Power conversion efficiency (PCE) decreased from 1.38% to 0.32% when the substrate temperature increased from 25
  Keywords: organic thin-film photovoltaic; electrospray; active layer; deposition; substrate temperatures.
  
  
• Performance evaluation of synthesized mono and hybrid nanofluids with minimum quantity lubrication in bearing steel turning operation: a sustainable ecofriendly machining  
  by Anup A. Junankar, Jayant K. Purohit, Nikhil V. Bhende 
  Abstract: Metal cutting industries are marching towards sustainable ecofriendly manufacturing processes. Nanofluid along with minimum quantity lubrication is the vital combination in the domain of sustainable manufacturing. The important objective of this experimental investigation was to evaluate the effect of synthesized monotype (Al2O3 and CuO) and hybrid (Al2O3/CuO) nanofluid along with minimum quantity lubrication on bearing steel turning by varying the cooling conditions. L9 orthogonal array utilized to perform the experimentation. The response variables surface roughness and cutting zone temperature were selected. The cutting speed, feed rate and depth of cut were selected as an input variables. For multi-objective optimization, grey relational analysis technique was utilized to find the optimum condition. Experimentation resulted that hybrid nanofluid (Al2O3/CuO) with minimum quantity lubrication observed as the most effective cooling condition. The response variables surface roughness and cutting zone temperature significantly decreased as under Al2O3/CuO hybrid nanofluid compared to Al2O3 and CuO nanofluid cooling condition.
  Keywords: Hybrid nanofluid; Minimum quantity lubrication; Grey relational analysis.
  
  
• Surface topography simulation and roughness prediction of micro-milling single crystal copper
  by Xiaohong Lu, Xvdong Sun, Pengrong Hou, Liang Xue, Steven Y. Liang 
  Abstract: To meet the requirements for assembly accuracy, service life and electric conductivity, the industry usually pursues low surface roughness of single-crystal copper micro-components. The processing and manufacturing of low-surface-roughness single crystal copper micro-components pose new challenges to the process. Micro-milling technology is an effective technical method for processing small parts with complex three-dimensional topography and low surface roughness. However, the surface forming mechanism of micro-milled single crystal copper is not clear. Based on the theory of trochoidal trajectory of micro-milling cutter, considering the influence of cutter vibration, cutter geometry, minimum cutting thickness and other factors, the formation mechanism of surface topography of single crystal copper micro-milling was analyzed, and a surface topography simulation model was established. The prediction of surface roughness was realized, and a single crystal copper groove milling experiment was carried out to verify the validity of the model and prediction.
  Keywords: micro-milling; single crystal copper; surface topography; surface roughness