Research on Parameter Optimization of Micro-Milling Al7075 Based on Edge-Size-Effect

Area of Science:

• Manufacturing Engineering
• Materials Science

Background:

• Micro-milling involves edge-size effects when cutting parameters approach the tool's edge radius (r₀).
• This effect can reduce cutting efficiency and degrade the surface quality of micro-slots.

Purpose of the Study:

• To investigate the influence of edge-size effects on micro-milling processes.
• To determine optimal cutting parameters for improved micro-slot surface quality and efficiency.

Main Methods:

• Conducted micro-milling experiments on Al7075-T6 materials.
• Analyzed milling forces in plough and shear zones.
• Determined minimum cutting thickness (hmin) range as 0.2r₀-0.4r₀.
• Studied the effect of feed rate per tooth to edge radius ratio (fz/r₀) on burr formation, surface roughness (Ra), and milling forces.
• Established micro-milling size-effect bands (strong, transition, weak).

Main Results:

• Identified a minimum cutting thickness range (0.2r₀-0.4r₀) influenced by tool edge radius.
• Established distinct size-effect zones (strong, transition, weak) based on fz/r₀.
• Demonstrated that avoiding the strong size-effect zone is key for optimizing micro-milling.
• Observed significant differences in top burr formation, bottom surface roughness (Ra), and milling forces between strong and weak size-effect zones.

Conclusions:

• The edge-size-effect is a critical factor in micro-milling, particularly at smaller cutting parameters.
• Optimizing micro-milling involves avoiding the strong edge-size-effect zone to enhance surface quality and efficiency.
• Findings provide a theoretical basis for selecting micro-milling parameters and improving surface quality.