Implementation of Sustainable Vegetable-Oil-Based Minimum Quantity Cooling Lubrication (MQCL) Machining of Titanium Alloy with Coated Tools

Abstract

The lubrication capacity and penetration ability of the minimum quantity cooling lubrication-based strategy is linked with lubrication specific parameters (oil flow rates and air pressure), cutting conditions, and chip formation. It points out the complex selection involved in the MQCL-assisted strategy to attain optimal machining performance. Lubrication during metal cutting operations is a complex phenomenon, as it is a strong function of the cutting conditions. In addition, it also depends on the physical properties of the lubricant and chemical interactions. Minimum Quantity Lubrication (MQL) has been criticized due to the absence of cooling parts; MQCL is a modified version where a cooling part in the form of sub-zero temperatures is provided. The aim of this paper was to investigate the influence of different lubrication flow parameters under minimum quantity cooling lubrication (MQCL) when machining aeronautic titanium alloy (Ti6Al4V) using Titanium Aluminum Nitride – Physical Vapor Deposition (TiAlN-PVD) coated cutting inserts. The machining experiments on the MQCL system were performed with different levels of oil flow rates (70, 90, and 100 mL/h) and the performance was compared with the conventional dry cutting and flood cooling settings. A generic trend was observed that increasing the oil flow rate from 70—mL/h to 100 h/h improved the surface finish and reduced thermal softening at a low feed of 0.1 mm/rev. The results revealed that many tool-wear mechanisms such as adhesion, micro-abrasion, edge chipping, notch wear, built-up edge (BUE), and built-up layer (BUL) existed.

Conventional and Recent Advances of Vegetable Oils as Metalworking Fluids (MWFs): A Review

“…Several advanced MQL approaches are currently available, including minimum quantity cooling lubrication (MQCL), hybrid MQL+ CO 2 lubrication, solid-lubricant-assisted MQL, MQL with nano-fluids, oil on water droplet MQL, and electrostatic minimum quantity lubrication (EMQL) [65][66][67][68][69][70]. While MQCL has gained popularity in the industry, its performance is highly dependent on specific MQL parameters such as droplet size, air flow, and nozzle distance from the cutting zone [71,72].…”

Understanding the Relationship between Surface Quality and Chip Morphology under Sustainable Cutting Environments

“…This aligns with the nomenclature of the procedure, indicating that it pertains to the MQL method. A nozzle, which is part of an MQL system, is responsible for directing pressurized air into the specific region where the workpiece and the tool are situated, as shown in Figure 1 [17]. On the other hand, some studies stated that during milling in different cryogenic temperatures, cutting forces increase due to the increase in material microhardness, and surface roughness decreases due to the chip formation that varies according to thermo-mechanical combination impact [18][19][20].…”

Evaluation of crude watermelon oil as lubricant in cylindrical turning of AISI 1525 steel employing Taguchi and grey relational analyses techniques

“…It was discovered that adding a tiny amount of lubricant—50 mL/h—yields a greater tool lifespan than dry cutting. Pervaiz et al [ 32 ] examined the effects of various lubricating flow conditions while utilizing TiAlN-PVD coated tools to machine Ti6Al4V. At a low FR of 0.1 mm/rev, it was found that raising the flow rate of oil from 70 mL/h to 100 mL/h enhanced the surface finish and decreased thermal softening.…”