Minimum quantity lubrication machining of aeronautical materials using carbon group nanolubricant: From mechanisms to application

TLDR

Sustainable manufacturing is shifting from flood and dry machining to minimum quantity lubrication (MQL), yet for aeronautical difficult‑to‑machine alloys MQL fails to provide adequate cooling and lubrication because of high heat generation, and the underlying mechanisms at the high‑temperature, high‑pressure tool–workpiece interface remain poorly understood. This study quantitatively assesses tribological characteristics—force, tool wear, chip morphology, and surface integrity—in titanium and nickel alloy machining with carbon‑group nano‑enhancers (CGNs) and systematically investigates the mechanisms, while proposing future directions to improve CGN thermal stability, activity, atomization, and intelligent processing solutions. Nano‑biolubricants, particularly non‑toxic carbon‑group nano‑enhancers, are employed to overcome the cooling and lubrication bottleneck, and the research evaluates their tribological performance through comprehensive force, wear, chip, and surface analyses. The findings establish an evaluation standard covering antifriction, antiwear, tool‑failure, material‑removal, and surface‑formation mechanisms of MQL, reveal the unique film‑.

Abstract

It is an inevitable trend of sustainable manufacturing to replace flood and dry machining with minimum quantity lubrication (MQL) technology. Nevertheless, for aeronautical difficult-to-machine materials, MQL couldn't meet the high demand of cooling and lubrication due to high heat generation during machining. Nano-biolubricants, especially non-toxic carbon group nano-enhancers (CGNs) are used, can solve this technical bottleneck. However, the machining mechanisms under lubrication of CGNs are unclear at complex interface between tool and workpiece, which characterized by high temperature, pressure, and speed, limited its application in factories and necessitates in-depth understanding. To fill this gap, this study concentrates on the comprehensive quantitative assessment of tribological characteristics based on force, tool wear, chip, and surface integrity in titanium alloy and nickel alloy machining and attempts to answer mechanisms systematically. First, to establish evaluation standard, the cutting mechanisms and performance improvement behavior covering antifriction, antiwear, tool failure, material removal, and surface formation of MQL were revealed. Second, the unique film formation and lubrication behaviors of CGNs in MQL turning, milling, and grinding are concluded. The influence law of molecular structure and micromorphology of CGNs was also answered and optimized options were recommended by considering diverse boundary conditions. Finally, in view of CGNs limitations in MQL, the future development direction is proposed, which needs to be improved in thermal stability of lubricant, activity of CGNs, controllable atomization and transportation methods, and intelligent formation of processing technology solutions.