Novel cavitation fluid jet polishing process based on negative pressure effects

Area of Science:

• Materials Science
• Mechanical Engineering
• Surface Engineering

Background:

• Traditional abrasive fluid jet polishing (FJP) faces limitations including high-pressure requirements, unstable material removal rates, and issues with air turbulence and large polishing spots.
• These limitations restrict FJP's effectiveness, particularly for achieving ultra-smooth surfaces.

Purpose of the Study:

• To introduce and validate a novel cavitation fluid jet polishing (CFJP) method.
• To demonstrate CFJP's capability for high-efficiency polishing in a low-pressure environment on small-scale surfaces.
• To analyze the mechanisms behind CFJP and compare its performance against traditional FJP.

Main Methods:

• Development of specialized polishing equipment with a sealed chamber to generate cavitation effects in a negative pressure environment.
• Computational fluid dynamics (CFD) simulations to analyze flow behavior, cavitation, and surface removal mechanisms.
• Experimental validation involving polishing various materials under different parameters, including vertical and inclined CFJP configurations.

Main Results:

• CFJP successfully utilizes the collapse of cavitation bubbles to generate high-energy microjets and shock waves, enhancing material removal.
• Polishing experiments showed increased removal depth and decreased surface roughness with rising negative outlet pressures.
• Extended polishing times led to progressively smoother surfaces, with CFJP achieving comparable surface roughness to FJP.

Conclusions:

• CFJP offers a viable alternative to traditional FJP, enabling high material removal rates and smooth surfaces.
• The method operates effectively in a low-pressure environment with reduced energy consumption.
• CFJP demonstrates potential for efficient polishing of small-scale surfaces with compatible surface finish quality.