Investigation of Grinding Characteristic using Nanofluid Minimum Quantity Lubrication

Cong Mao,Xiaojun Tang,Hongfu Zou,Xiangming Huang,Zhixiong Zhou 한국정밀공학회 2012 International Journal of Precision Engineering and Vol. No.

Conventional grinding fluid is widely used in grinding process, which results in high consumption and impacting the environment. The promising alternative to conventional dry and fluid coolant application is minimum quantity lubrication (MQL). It is known that the cooling and lubrication performance of the grinding fluid is the key technical area for the success application of MQL grinding process. In this study, Water based Al2O3 nanofluid was applied to grinding process with MQL approach for its excellent convection heat transfer and thermal conductivity properties. The grinding characteristics of hardened AISI 52100 steel were investigated and compared with those of wet, dry and pure water MQL grinding. Experimental results show that water based Al2O3 nanofluid MQL grinding can significantly reduce the grinding temperature, decrease the grinding forces, improve the ground surface morphology and reduce the surface roughness in comparison to pure water MQL grinding. Furthermore, the cooling and lubricating mechanism for nanofluid MQL grinding was discussed in detail.

Experimental study on white layers in high-speed grinding of AISI52100 hardened steel

Xiangming Huang,Yinghui Ren,Zhixiong Zhou,Hang Xiao 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.3

Ground white layer structure is an untempered martensitic due to grinding heat and plastic deformation. Many researchers have studiedthe formation of white layers at low grinding speed. However, few studies were found on white layer at high grinding speed. Therefore,to minimize white layer, it would be very useful to know the formation of white layer in the high-speed grinding. We performed grindingexperiments using hardened AISI52100 steel with cubic boron nitride (CBN). Grinding force and grinding temperature were onlinemeasured during grinding process. Surface roughness, residual stress and white layer were also examined, respectively. The influence ofgrinding wheel speed on grinding force and surface integrity was analyzed. Formation of white layer was also studied. Experimentalresults show that grinding force and plastic deformation decrease significantly at higher grinding speed. Meanwhile, white layer depthand residual stress value increase with the grinding wheel speed, and residual stress is well correlated with ground white layer depth. White layer during high-speed grinding process results from phase transformation due to grinding heat and rapid cooling, while the plasticdeformation may be ignored for the ground white layer.

Experimental investigations of machining characteristics of SiC in high speed plunge grinding

Chongjun Wu,Beizhi Li,Jianguo Yang,Steven Y. Liang 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.3

Grinding is widely used as a productive technique for finishing ceramic components in the manufacturing industry. However,it is still difficult to achieve a satisfying finishing quality for scarce of comprehensive engineering investigations of damage-freeand economical techniques of advanced ceramics. This paper will utilize a high speed grinder to develop the grinding forces,temperature, grinding surface and subsurface features in high speed plunge grinding of SiC. The ductile grinding of SiC undera relatively high grinding speed will be investigated. A set of detecting equipment, including a rotating dynamometer and agrindable thermocouple, will be used to measure the online grinding forces and temperature. Besides, the subsurface damage,chips and ground surface will be examined by SEM micrographs. It has been found that ductile grinding of SiC can beachieved through a combination of the increase of the wheel speed and the control of grinding parameters. Via causing lowerforce and thermal effects, the critical value for ductile grinding of SiC can be greatly improved under high speed grindingcomparing to conventional speed grinding. Moreover, the grinding subsurface integrity will not be adversely effected thoughimproving material removal volumes under high speed grinding.

Evaluation of the effects of machining parameters on MQL based surface grinding process using response surface methodology

Rahul R. Chakule,Sharad S. Chaudhari,P. S. Talmale 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.8

Grinding is a precision machining process widely used for close tolerance and good surface finish. Due to aggregate of geometrically undefined cutting edges and material removal in the form of microchips, grinding requires more specific energy as friction is greater in the grinding interface. The optimum use and proper penetration of coolant is the prime requirement which is achieved by effective cooling and lubrication. In this research, a greater focus is on MQL technique, which is economical and eco-friendly. The paper presents important aspects of the grinding process considering the surface roughness and cutting force. The experiments were carried out on horizontal surface grinding machine using Response surface methodology (RSM). In addition, evaluation of grinding performance parameters like coefficient of friction, cutting forces, temperature and specific grinding energy for different machining environments has been discussed. The lowest surface roughness and coefficient of friction observed was 0.1236 µm and 0.3906, respectively for MQL grinding, whereas lowest specific grinding energy was found as 18.95 N/mm 2 in wet grinding. The temperature recorded in MQL grinding was 29.07 °C, which is marginally higher than wet condition. The response obtained as cutting forces, temperature and surface roughness under MQL mode encourages its use for machining AISI D3 type material compared to other grinding environments. Mathematical modeling showing the relation between the factors and response variables was established using Response surface methodology. Regression analysis was performed to determine the accuracy of mathematical model, significant factors and interaction effects of parameters on responses.

Analytical Modelling of Temperature in Cylindrical Grinding to Predict Grinding Burns

Azhar Thanedar,Ganesh G. Dongre,Suhas S. Joshi 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.1

The direct measurement of grinding temperature is always difficult due to coolant cover and very size of work and wheel interaction zone. At the same time, high heat generation in grinding often leads to grinding burns thereby affecting surface integrity; in this context, theoretical evaluation of temperature could facilitate early detection of the grinding burns. This paper therefore presents an analytical model to evaluate grinding temperature and correlates it with the occurrence of grinding burns in terms of BNA. In general, the analytical approach involves evaluating real contact length, grinding forces and finally grinding zone temperature for the plunge cylindrical grinding. The maximum rise in grinding temperature at the surface was calculated, for the wet grinding process by considering the total heat flux entering into the grinding system. Model validation experiments have been performed to measure BNA and identify parametric conditions that produce grinding burns. The model estimate of grinding zone temperature of 631 °C is in good agreement (92%) with other research works. Further, when the calculated grinding temperature reaches beyond 631 °C, the grinding burns are observed on the work surface with a BNA value of the order of 100 mp for the micro alloyed steel. The minimum thermal damage in terms of BNA is observed at higher levels of wheel speed and spark-out time and lower levels of depth of cut.

Ultra-Fine Grinding Mechanism of Inorganic Powders in a Stirred Ball Mill : Examination of Grinding Kinetics of Using Grinding Aids

Choi, Hee Kyu,Choi, Woo Sik 한국화학공학회 2003 Korean Journal of Chemical Engineering Vol.20 No.4

Recently, in various industrial processes, the need for fine particles, especially submicron-sized particles, has increased in the field of preparing raw powders such as fine ceramics and high value added products. Therefore, the research in fine grinding has gained more importance, especially, in submicron grinding. In the previous paper, a series of wet grinding experiments using inorganic powders by a stirred ball mill were performed. The grinding consumption power was measured, and the grinding rate constant, K, in the grinding kinetics equation was examined, based on a grinding kinetics analysis of experimental specific surface area with particle size distribution of ground products obtained under various grinding conditions. Also the effect of grinding aids on grinding rate constant K was investigated. It was confirmed that the grinding rate constant K, when using grinding aids improved by 1.95% and 25.6% for a 60 wt% and 70wt% slurry concentrate, respectively, when compared with the case of the absence of grinding aids. It was found that grinding aids have an important effect on increasing the grinding rate, especially for a slurry of high concentration.

CFRP Grinding Wheels for High Speed and Ultra-High Speed Grinding: A Review of Current Technologies and Research Strategies

Lu Yang,Chih-Hsing Chu,Yu-Can Fu,Jiu-Hua Xu,Yong-Tao Liu 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.

This paper primarily reviews the general condition of research on and applications of high speed and ultra-high speed grinding technology. Both technical requirements for grinding wheels used for high speed and ultra-high speed grinding, and existing problems with the current processes are pointed out. Specific to these problems, the discussion regarding high-performance lightweight grinding wheels with a carbon fiber reinforced plastic (CFRP) substrate focuses on three aspects, i.e., design and manufacture, experimental grinding research, and practical industrial applications. Based on the summary of existing research and the application status of the CFRP grinding wheel, existing deficiencies are qualitatively discussed. Focusing on the development of a lightweight CFRP grinding wheel for high speed and ultra-high speed grinding at the end of the paper, some key technical problems with CFRP substrate grinding wheels, such as controlled performance, controlled shape, and the grinding mechanism, are identified, along with further research strategies to resolve them.

Dry Grinding by Means of Additively Manufactured Toric Grinding Pins

Michael Keitel,Berend Denkena,Benjamin Bergmann 한국정밀공학회 2024 International Journal of Precision Engineering and Vol.11 No.2

The dry grinding process is challenging due to the induced thermal loads into the workpiece, which leads to a reduction of the workpiece quality. One approach to reduce the thermal loads is to adjust the grinding tool geometry by inserting a porous structure for dry grinding. This porous structure can be implemented, for example, by additively manufactured grinding tools. For this purpose, the suitability of additively manufactured vitrified cubic boron nitride grinding tools for dry grinding of tempered AISI M3:2 was investigated and compared with conventionally manufactured grinding tools to investigate the possibility of reducing the high temperatures and to verify the advantage of additively manufactured grinding tools. For this the resulting topographies and residuals stress states as well as wear of the grinding tools were analyzed. Additively manufactured grinding tools generated constant surface roughnesses of below 1 µm as well as contant compressive residual stress states. These results were attributed to a continuous self-sharpening of the grinding tools, which was shown qualitatively and quantitatively on the basis of the tool surfaces. Additively manufactured grinding tools with a porous structure thus have the potential to increase the possibilities of dry grinding.

원통연삭시 연삭휠의 종류에 따른 연삭 가공특성에 관한 연구

이충석(Choong-Seok Lee),채승수(Seung-Su Chae),김택수(Taeck-Su Kim),이상민(Sang-Min Lee),박휘근(Hwi-Keun Park),이종찬(Jong-Chan Lee) 한국기계가공학회 2008 한국기계가공학회지 Vol.7 No.1

This paper reports some experimental results of cylindrical external grinding using CBN wheels. Many experimental studies for surface grinding have been done, but not for the cylindrical grinding due to the difficulty of grinding force measurement. In this paper a new experimental device has been proposed for the grinding force measurement in cylindrical grinding. The cylindrical grinding experiments were carried out at various grinding conditions with several CBN grinding wheels. The experimental results indicate that the CBN wheels with smaller grains result in the higher grinding forces in both SCM415 and STD11 workpieces. The grinding forces of all wheels were proportional to the infeed speeds and the difference of each wheels was prominent at high infeed speed for SCM415.

Materials (organic, inorganic, Electronic, Thin Films), Polymer, Fluidization, Particle Technology : Ultra-Fine Grinding Mechanism of Inorganic Powders in a Stirred Ball Mill - Examination of Grinding Kinetics of Using Grinding Aids -

( Hee Kyu Choi ),( Woo Sik Choi ) 한국화학공학회 2003 Korean Journal of Chemical Engineering Vol.20 No.4

Recently, in various industrial processes, the need for fine particles, especially submicron-sized particles, has increased in the field of preparing raw powders such as fine ceramics and high value added products. Therefore, the research in fine grinding has gained more importance, especially, in submicron grinding. In the previous paper, a series of wet grinding experiments using inorganic powders by a stirred ball mill were performed. The grinding consumption power was measured, and the grinding rate constant, K, in the grinding kinetics equation was examined, based on a grinding kinetics analysis of experimental specific surface area with particle size distribution of ground products obtained under various grinding conditions. Also the effect of grinding aids on grinding rate constant K was investigated. It was confirmed that the grinding rate constant K, when using grinding aids improved by 1.95% and 25.6% for a 60 wt% and 70wt% slurry concentrate, respectively, when compared with the case of the absence of grinding aids. It was found that grinding aids have an important effect on increasing the grinding rate, especially for a slurry of high concentration.