An assessment of environmentally conscious lubrication techniques in grinding: use of minimum quantity lubrication, solid lubricants and cryogenic cooling

Abstract This paper presents the machining of Ti6Al4V Integral Blade Rotors (IBR) using CO2 as cryogenic cooling. This kind of component is typical in gas turbines, pumps and other rotary machines. Flank milling technique using diamond polycrystalline (PCD) tools using CO2 and Minimum Quantity Lubrication (MQL), denominated CryoMQL, is an alternative to conventional oil emulsions. The proposed approach implies a balance between technical and environmental issues, and it makes feasible the use PCD tools avoiding the high temperature reactivity of Ti6Al4V alloy with this type of cutting tools. CO2 must be supplied and injected onto the cutting zone, avoiding the risks of dry ice formation and clogging of both pipes and nozzles. For this purpose, a new device for CO2 delivery was developed, using gas and liquid CO2.

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Environmentally conscious machining of Inconel 718 with solid lubricant assisted minimum quantity lubrication

Metal Powder Report ◽

10.1016/j.mprp.2020.08.008 ◽

2020 ◽

Author(s):

M.A. Makhesana ◽

K.M. Patel ◽

B.K. Mawandiya

Keyword(s):

Inconel 718 ◽

Solid Lubricant ◽

Minimum Quantity Lubrication ◽

Environmentally Conscious ◽

Minimum Quantity

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Experimental Results on Lamellar-Type Solid Lubricants in Enhancing Minimum Quantity Lubrication Machining

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4033995 ◽

2016 ◽

Vol 138 (10) ◽

Cited By ~ 2

Author(s):

Trung Kien Nguyen ◽

Kyung-Hee Park ◽

Patrick Y. Kwon

Keyword(s):

Vegetable Oil ◽

Solid Lubricant ◽

Minimum Quantity Lubrication ◽

Solid Lubricants ◽

Machining Process ◽

Minimum Quantity ◽

Aspect Ratios ◽

Significant Difference ◽

1045 Steel ◽

Lamellar Type

This paper studies the effect of various lamellar-type solid lubricants (graphite and hBN) that can be mixed into a lubricant to potentially improve the machinability of minimum quantity lubrication (MQL) machining. To examine this, the solid lubricants are classified into particles and platelets based on their aspect ratios as well as their respective sizes. In particular, the particles are classified into microparticles and nanoparticles based on their dimensions (average radius), while the platelets were classified, based on their average thickness, into two types: the “microplatelets” if the thickness is typically up to few tens of microns and the “nanoplatelets” if the thickness is well below a tenth of a micron (even down to few nanometers). Our previous work has shown that the mixture of an extremely small amount (about 0.1 wt. %) of the graphitic nanoplatelets and vegetable oil immensely enhanced the machinability of MQL machining. In this paper, many lubricants, each mixed with a particular variety of nano- or micro-platelets or one type of nanoparticles, were studied to reveal the effect of each solid lubricant on MQL machining. Prior to the MQL machining experiment, the tribological test was conducted to show that the nanoplatelets are overall more effective than the microplatelets and nanoparticles in minimizing wear despite of no significant difference in friction compared to pure vegetable oil. Consequently, the MQL ball-milling experiment was conducted with AISI 1045 steel yielding a similar trend. Surprisingly, the oil mixtures with the microplatelets increased flank wear, even compared to the pure oil lubricant when the tools with the smooth surface were used. Thus, the nanoscale thickness of these platelets is a critical requirement for the solid lubricants in enhancing the MQL machining process. However, maintaining the nanoscale thickness is not critical with the tools with the rough surfaces in enhancing the MQL process. Therefore, it is concluded that finding an optimum solid lubricant depends on not only the characteristics (material as well as morphology) of solid lubricants but also the characteristic of tool surface.

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A Critical Factor in Enhancement of MQL Lubricants: Platelet Thickness

Volume 2: Systems; Micro and Nano Technologies; Sustainable Manufacturing ◽

10.1115/msec2013-1145 ◽

2013 ◽

Author(s):

Trung Kien Nguyen ◽

Patrick Y. Kwon ◽

Kyung-Hee Park

Keyword(s):

Tool Wear ◽

Vegetable Oil ◽

Ball Mill ◽

Minimum Quantity Lubrication ◽

Critical Factor ◽

Solid Lubricants ◽

Minimum Quantity ◽

Lamellar Type

The lamellar-type solid lubricants are readily available in a form of platelets. The diameter and thickness of these platelets are typically up to tens of microns and few microns, respectively, which are classified as micro-platelets. Some of these platelets are also available as nano-platelets whose thickness is well below a micron (even to few nanometers). In the previous work, the vegetable oil mixed with nano-platelets was enormously effective for Minimum Quantity Lubrication (MQL) machining. Clearly, the micro-platelets are not as inexpensive. In addition, the mixtures with the micro-platelets are not as stable as those with the nano-platelets. This paper intends to find the effect of the thickness differential on these platelets in MQL machining. The tribometer test shows that the nano-platelets are much more effective than the micro-platelets in reducing wear without changing the friction. With the MQL ball mill experiment, the micro-platelets present in MQL oil increased the tool wear, even compared to the traditional MQL with pure oil only. Thus, the thickness of the nano-platelets holds an important characteristic to enhance MQL-based machining.

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Progressing towards Sustainable Machining of Steels: A Detailed Review

Materials ◽

10.3390/ma14185162 ◽

2021 ◽

Vol 14 (18) ◽

pp. 5162

Author(s):

Kashif Ishfaq ◽

Irfan Anjum ◽

Catalin Iulian Pruncu ◽

Muhammad Amjad ◽

M. Saravana Kumar ◽

...

Keyword(s):

Skin Diseases ◽

Cryogenic Treatment ◽

Sustainable Manufacturing ◽

Health And Safety ◽

Minimum Quantity Lubrication ◽

Solid Lubricants ◽

Cryogenic Cooling ◽

Cutting Fluid ◽

Dry Cutting ◽

Sustainable Machining

Machining operations are very common for the production of auto parts, i.e., connecting rods, crankshafts, etc. In machining, the use of cutting oil is very necessary, but it leads to higher machining costs and environmental problems. About 17% of the cost of any product is associated with cutting fluid, and about 80% of skin diseases are due to mist and fumes generated by cutting oils. Environmental legislation and operators’ safety demand the minimal use of cutting fluid and proper disposal of used cutting oil. The disposal cost is huge, about two times higher than the machining cost. To improve occupational health and safety and the reduction of product costs, companies are moving towards sustainable manufacturing. Therefore, this review article emphasizes the sustainable machining aspects of steel by employing techniques that require the minimal use of cutting oils, i.e., minimum quantity lubrication, and other efficient techniques like cryogenic cooling, dry cutting, solid lubricants, air/vapor/gas cooling, and cryogenic treatment. Cryogenic treatment on tools and the use of vegetable oils or biodegradable oils instead of mineral oils are used as primary techniques to enhance the overall part quality, which leads to longer tool life with no negative impacts on the environment. To further help the manufacturing community in progressing towards industry 4.0 and obtaining net-zero emissions, in this paper, we present a comprehensive review of the recent, state of the art sustainable techniques used for machining steel materials/components by which the industry can massively improve their product quality and production.

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