Biological Stability of Water-Based Cutting Fluids: Progress and Application

The application of cutting fluid in the field of engineering manufacturing has a history of hundreds of years, and it plays a vital role in the processing efficiency and surface quality of parts. Among them, water-based cutting fluid accounts for more than 90% of the consumption of cutting fluid. However, long-term recycling of water-based cutting fluid could easily cause deterioration, and the breeding of bacteria could cause the cutting fluid to fail, increase manufacturing costs, and even endanger the health of workers. Traditional bactericides could improve the biological stability of cutting fluids, but they are toxic to the environment and do not conform to the development trend of low-carbon manufacturing. Low-carbon manufacturing is inevitable and the direction of sustainable manufacturing. The use of nanomaterials, transition metal complexes, and physical sterilization methods on the bacterial cell membrane and genetic material could effectively solve this problem. In this article, the mechanism of action of additives and microbial metabolites was first analyzed. Then, the denaturation mechanism of traditional bactericides on the target protein and the effect of sterilization efficiency were summarized. Further, the mechanism of nanomaterials disrupting cell membrane potential was discussed. The effects of lipophilicity and the atomic number of transition metal complexes on cell membrane penetration were also summarized, and the effects of ultraviolet rays and ozone on the destruction of bacterial genetic material were reviewed. In other words, the bactericidal performance, hazard, degradability, and economics of various sterilization methods were comprehensively evaluated, and the potential development direction of improving the biological stability of cutting fluid was proposed.

Investigations on the effect of silver nanoparticles on performance of coconut oil based cutting fluid in minimal fluid application

In this work, an innovative nanocutting fluid, based on coconut oil was developed by dispersing silver nanoparticles (AgNPs) of size less than 50 nm. The tribological and physical properties of the prepared nanocutting fluid with different volumes of silver nanoparticles were studied. It was found that the addition of 4% by volume of nanoparticles enhanced the properties of the nanocutting fluid compared to the other concentrations studied, thus demonstrating its excellent tribological performance. The effect of the newly developed nanocutting fluid with 4% of silver nanoparticles on cutting performance was also investigated while machining AISI4340 steel with minimal fluid application. Results revealed that the cutting force, cutting temperature, and tool wear are reduced on an average by 22.6%, 12.6%, and 5.3% respectively. It was evident that efficient cooling and lubrication of nanocutting fluid dispersed with silver nanoparticles improved the cutting performance. The outcomes of this work can be considered as a development toward eco-friendly and sustainable machining.

Tool Wear Behavior in μ-turning of Nimonic 90 Under Vegetable Oil-Based Cutting Fluid

The characteristics such as high hardness and shear modulus, low thermal conductivity, strain hardening of Nickel-based superalloys lead to high machining forces and temperature, poor surface quality and integrity, rapid tool wear, etc. The present article investigates the tool wear mechanism of the tungsten carbide (WC) tool in µ-turning of Nimonic 90 under dry, wet, and vegetable oil-based cutting fluid (VCF). Canola oil is used as vegetable oil. Three different combinations of cutting speed, feed rate, and depth of cut are considered for analysis. The tool wear is characterized using optical and scanning electron microscopy. Machining with VCF shows an approximate reduction of flank wear width in the range of 12%-52% compared to dry and wet conditions. The main wear mechanisms observed on the tool flank and rake face are abrasion, built-up edge adhesion, and edge chipping. The VCF considerably reduces the adhesion and abrasion and, hence, increases tool life. The chips produced in dry conditions are found fractured and uneven, whereas, it had an uneven lamella structure in wet conditions. The VCF found reducing the plastic deformation in each cutting condition, as a result, producing fine lamella structured chips.

Impact of cutting fluid on hybrid manufacturing of AISI H13 tool steel

Purpose This paper aims to analyse the effects derived from the presence of residual coolant from machining operations on the Directed Energy Deposition of AISI H13 tool steel and the quality of the resulting part. Design/methodology/approach In the present paper, the effectiveness of various cleaning techniques, including laser vaporising and air blasting, applied to different water/oil concentrations are studied. For this purpose, single-layer and multi-layer depositions are performed. Besides, the influence of the powder adhered to the coolant residues remaining on the surface of the workpiece is analysed. In all cases, cross-sections are studied in-depth, including metallographic, microhardness, scanning electron microscopy and crack mechanism analyses. Findings The results show that, although no significant differences were found for low oil concentrations when remarkably high oil concentrations were used the deposited material cracked, regardless of the cleaning technique applied. The crack initiation and propagation mechanisms have been analysed, concluding that the presence of oil leads to hydrogen induced cracking. Originality/value High oil concentration residues from previous machining operations in hybrid manufacturing led to hydrogen induced cracking when working with AISI H13 tool steel. The results obtained will help in defining future hybrid manufacturing processes that combine additive and subtractive operations.

Development of a tool module for external intermittent grinding with the activation of the cutting fluid

An instrumental module for external circular grinding has been developed, using methods of intermittent processing with replaceable abrasive bars with a combined supply of coolant through the pores of the bars and through the channels between them, with its activation in special cavitation nozzles. Is to develop a method for circular external inter-mittent grinding and a tool module that ensures stable operation of the wheel and efficient supply of cutting fluid to the cutting zone. The tool module of the assembling grinding wheel has been developed, which provides the effect of intermittent grinding with the supply of cutting fluid through the abrasive bars and the gap between them.

Application of TOPSIS Method for Prediction of Optimum Design Parameters of Micro Hole Textured Cutting Inserts in Turning of Al-MMC

Metal Matrix Composite (MMC) has better mechanical properties and it is possible to produce near net shape. Aluminum-based MMC (Al-MMC) has challenges in terms of machinability studies and estimation of its optimum process parameters. Alternative cutting fluid research is a challenging area in machining. To avoid, existing hydrocarbon oil-based cutting fluid, textured inserts embedded with a solid lubricant are one of the alternative solutions. Micro hole textured inserts make a hole on the rake face of the cutting tool inserts. Texture includes various important design parameters namely hole diameter, hole depth and pitch between the holes. These optimum parameters influence the machining process. In this work, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method is used to find the optimum design parameters (hole diameter, hole depth and pitch between holes) during turning of Al- MMC. The objective parameters considered are minimization of surface roughness, power consumption and tool flank wear. The optimum combination of these design parameters is obtained by the higher relative closeness value of the TOPSIS method. The result of the investigation revealed that these design parameters are important to obtain improved machining performance. Also, it is understood that the TOPSIS method has an appropriate procedure to solve multiple objective optimization problems in manufacturing industries.