Effect of Graphene nanoplatelets (GNP) reinforcement on grindability of zirconium diboride ceramics

Author(s):  
Nagaraj Shanbhog ◽  
Arunachalam N ◽  
Srinivasa Rao Bakshi

Abstract The grindability of graphene nanoplatelets (GNP) reinforced ZrB2 was studied using resin bonded diamond grinding wheel under dry and wet conditions. A comparative study of grinding forces was performed at selected wheel surface speeds and depth of cuts for surface grinding. ZrB2-GNP showed lower normal grinding forces due to the reduced hardness. The presence of GNP reinforcement in ZrB2 resulted in lower tangential forces and reduced specific grinding energy due to the role of GNP as solid lubricant. The measured forces showed good correlation with the micro cutting model for ZrB2 and ZrB2-GNP under dry condition. The tangential forces showed same trend as normal forces at different depth of cuts and wheel surface speeds for both ZrB2 and ZrB2-GNP with average force ratios of 0.3 and 0.35 respectively. The presence of porosity in ZrB2 increased the normal grinding forces during wet grinding. Scanning Electron Microscope (SEM) images of the grinding chips indicated a mixture of both the ductile mode and the brittle mode of material removal with predominantly brittle fractured chips. Energy Dispersive Spectroscopy (EDS) confirmed the presence of GNPs in ZrB2-GNP grinding chips. The topography of the grinding wheel showed higher wheel loading after the dry grinding than that of wet grinding. The wet grinding resulted in relatively lower surface roughness (Ra values) compared to that of dry grinding.

2018 ◽  
Vol 198 ◽  
pp. 02004
Author(s):  
Junping Zhang ◽  
Weidong Wang ◽  
Songhua Li ◽  
Han Tao

The impacts of different linear speed of grinding wheel, grinding depth and workpiece feed speed with or without grinding fluid on grinding force were studied by plane grinding machining of zirconia ceramics. The impacts of different machining environment and grinding parameter on normal and tangential grinding forceswere studied by testing the grinding force during grinding with a force measuring device. The studies showed that the normal and tangential grinding forces decrease with the increase of the linear speed of grinding wheel and increase with the improvement of grinding depth and workpiece feed speed. The grinding depth has the greatest impacts on the normal and tangential grinding forces in dry grinding environment; while in wet grinding environment, the grinding depth exerts the greatest impacts on the normal grinding force and the linear speed of grinding wheel imposes the greatest impacts on the tangential grinding force. In addition, it was found that the normal grinding force in dry grinding is minor than that in wet grinding, that the tangential grinding force in dry grinding is greater than that in wet grinding, and that the grinding force ratio in dry grinding is lower than that in wet grinding.


2008 ◽  
Vol 389-390 ◽  
pp. 24-29 ◽  
Author(s):  
H.P. Yuan ◽  
Hang Gao ◽  
Yong Jie Bao ◽  
Yong Bo Wu

Aiming at solving the problems of wheel loading in dry grinding of Carbon/Epoxy composite materials, a novel electroplated grinding wheel with controlled abrasive cluster was developed, in which the diameter of clusters is in Φ0.2 mm to Φ1.0 mm and the interspace between them is about 0.5 mm to 1.0 mm. A conventional electroplated grinding wheel with abrasive grains distributed randomly was fabricated in the same way. The comparison experiments involving C/E composite were conducted on a vertical spindle grinder with the novel and conventional grinding wheels. The results show that the grinding forces of novel wheel developed is more lower though little larger surface roughness, and the wheel loading phenomenon is markedly decreased compared with conventional electroplated wheel.


2020 ◽  
Vol 4 (4) ◽  
pp. 114
Author(s):  
Akira Mizobuchi ◽  
Atsuyoshi Tashima

This study addresses the wet grinding of large stainless steel sheets, because it is difficult to subject them to dry grinding. Because stainless steel has a low thermal conductivity and a high coefficient of thermal expansion, it easily causes grinding burn and thermal deformation while dry grinding on the wheel without applying a cooling effect. Therefore, wet grinding is a better alternative. In this study, we made several types of grinding wheels, performed the wet grinding of stainless steel sheets, and identified the wheels most suitable for the process. As such, this study developed a special accessory that could be attached to a wet grinding workpiece. The attachment can maintain constant pressure, rotational speed, and supply grinding fluid during work. A set of experiments was conducted to see how some grinding wheels subjected to some grinding conditions affected the surface roughness of a workpiece made of a stainless steel sheet (SUS 304, according to Japanese Industrial Standards: JIS). It was found that the roughness of the sheet could be minimized when a polyvinyl alcohol (PVA) grinding wheel was used as the grinding wheel and tap water was used as the grinding fluid at an attachment pressure of 0.2 MPa and a rotational speed of 150 rpm. It was shown that a surface roughness of up to 0.3 μm in terms of the arithmetic average height could be achieved if the above conditions were satisfied during wet grinding. The final surface roughness was 0.03 μm after finish polishing by buffing. Since the wet grinding of steel has yet to be studied in detail, this article will serve as a valuable reference.


2016 ◽  
Vol 874 ◽  
pp. 101-108 ◽  
Author(s):  
Amir Daneshi ◽  
Bahman Azarhoushang

Structuring of the grinding wheels is a promising method to reduce the forces involved in grinding, especially during dry grinding. In this paper, one of the methods of grinding wheel structuring is presented. The structuring process was modeled to find the corresponding dressing parameters for the desired structure dimensions. The cylindrical grinding operation with the structured wheels was simulated to produce a spiral free ground surface. Afterwards, the dry grinding experiments with the structured and non-structured wheels were carried out to evaluate the efficiency of the structured wheels. The results revealed that the grinding forces can be reduced by more than 50% when the grinding wheels are structured, while the surface roughness values increase by 80%.


2011 ◽  
Vol 325 ◽  
pp. 147-152
Author(s):  
Qiu Lin Niu ◽  
Guo Giang Guo ◽  
Xiao Jiang Cai ◽  
Zhi Qiang Liu ◽  
Ming Chen

As two kinds of advanced titanium alloys, TC18 and TA19 were introduced in this paper. The machinabilities of TC18 and TA19 alloys were described in the grinding process. Grinding experiments were completed using green silicon carbide grinding wheel with the coarser 100 grit. Grinding forces and specific energy in surface grinding were investigated. And then, for studying the grinding characteristic, SEM images of the workpiece material were obtained. The results indicated that specific chip formation had the great effect on the mechanism of grinding TC18 and TA19 alloys, and the scratch was the main characteristic of surface grinding. TC18 alloy had the poor grinding performance compared to TA19 alloy.


2014 ◽  
Vol 8 (4) ◽  
pp. 569-575 ◽  
Author(s):  
Masakazu Fujimoto ◽  
◽  
Yongbo Wu ◽  
Mitsuyoshi Nomura ◽  
Hidenari Kanai ◽  
...  

The objectives of this paper are to describe a quantitative evaluation of mini-size diamond grinding wheel surface topography in Ultrasonic Assisted Grinding (UAG) process and demonstrate the effects of topography on grinding characteristics. In this study, threedimensional (3D) analysis of the wheel working surface was observed using a Scanning Electron Microscope (SEM) with four electron probes (hereafter described as 3D-SEM) in an on-surface UAG process. These results indicated that a good wheel surface maintained in the UAG process is related to the number and the area of cutting edges. Additionally, the resulting topographic features of the grinding wheel surface are closely related to low grinding forces and allow easy manufacturing of a mirror workpiece surface.


Author(s):  
Hamed Adibi ◽  
S. M. Rezaei ◽  
Ahmed A. D. Sarhan

Wheel loading entails chip accumulation in porosities between grains or welding to the top of cutting grains. It is considered one of the most prevalent problems in grinding Nickel-based super alloys. Identification of wheel loading is an important issue for optimizing the dressing intervals, but it can be a time consuming and an expensive process. A novel technique based on digital image processing to determine the loading areas over the surface of CBN vitrified grinding wheels using the toolbox of MATLAB is presented in this paper. The optical characteristics of the metal chips, the abrasive grains and wheel bond are considered. Experiments were performed to examine the repeatability of the proposed technique. The results were verified by the use of a scanning electron microscope. Based on the proposed technique, the effects of cutting parameters on the loaded area to wheel surface ratio in relation to grinding performance were studied empirically.


2011 ◽  
Vol 487 ◽  
pp. 121-125 ◽  
Author(s):  
Xiao Hu Zheng ◽  
Z.Q. Liu ◽  
Guo Qiang Guo ◽  
Qing Long An ◽  
Ming Chen

Titanium alloy is widely used in aerospace and aircraft industries but it is a kind of difficult-to-cut material. In this paper, wet grinding and dry grinding of titanium alloy Ti-6Al-4V using green silicon carbide wheel were investigated. The specific tangential force and force ratio were calculated and surface roughness of machined surfaces was measured. The morphology of machined surface were observed by SEM. The experimental results showed that the specific tangential forces were big. The depth of cutting has greater influence on surface roughness than workpiece speed. The surface roughness of wet grinding was better than dry grinding. Micro cracks were observed on wet grinding. The main reason is the high temperature and quenching cracking.


2014 ◽  
Vol 1017 ◽  
pp. 237-242
Author(s):  
Heike Kitzig ◽  
Nima Jandaghi ◽  
Bahman Azarhoushang ◽  
Alireza Vesali

In order to decrease the negative environmental impacts of the cutting fluids (for example, disposal of grinding sludge) and also to reduce the manufacturing costs and the required space for the machines the dry grinding can be a conceivable alternative for the conventional grinding processes. Nevertheless, dry grinding has not been widely introduced into industry because of the high temperature generated in the grinding zone and difficulties of heat transfer without coolants. Selection of the proper grinding wheel bonds, grit sizes and concentration has significant effect on the grinding performance and the generated heat in the contact zone. This paper addresses the effects of the grinding wheel bond and the concentration on the dry grinding process efficiency through comparing the results of the carried out experiments with three resin bonded cBN-cup-wheels, each consisting different bond components. For this purpose, surface roughness and thermal damages during dry and wet grinding (utilizing grinding oil) by three different resin bonds were measured. The results show almost identical surface roughness values for dry and wet grinding. Furthermore, using the resin-kryolith-graphite bonded wheel leads to a reduction in thermal damages on the workpiece. Through different experiments, it was shown that the different bonds, used in this study, have significant influence on the chip loading of the grinding wheels. This is contributed to the different chip formation mechanisms and induced grinding temperatures when grinding by the different wheel bonds.


2010 ◽  
Vol 126-128 ◽  
pp. 353-358 ◽  
Author(s):  
Yunn Shiuan Liao ◽  
Y.P. Yu ◽  
C.H. Chang

The use of cutting fluid containing nano particles in wet grinding and MQL grinding of Ti-6A1-4V is studied. For comparison purpose, experiments by applying the general purpose water-based cutting fluid are also conducted. The loading of the grinding wheel and morphology of the ground surface are observed, and the grinding forces and roughness of the ground surface are measured for analysis. It is found that the use of cutting fluid containing nano particles results in less loading of the wheel and better ground surface as compared with those with the use of the general purpose water-based cutting fluid because of smaller grinding forces and coefficient of friction originated from “lotus effect” of nano particles. MQL leads to better results than wet grinding. This is attributed to the possibility of more nano particles to effectively reach the grinding zone by the assistance of the high pressure air of MQL, which in turns enhances the functions of nano particles in alleviating wheel loading and decreasing coefficient of friction. Based on the experimental results, it is concluded that the use of cutting fluid containing nano particles has positive effects on grinding. Especially the MQL, not only can it achieve the best performance, it is also cost effective and environmentally attractive.


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