Metallization of Porous Polyethylene Using a Wire-Arc Spray Process for Heat Transfer Applications

Area of Science:

• Materials Science
• Polymer Science
• Surface Engineering

Background:

• Metallizing low melting point polymers like polyethylene (PE) via thermal spraying is challenging.
• Traditional methods struggle with PE's softness and low thermal stability.

Purpose of the Study:

• To investigate the feasibility of metallizing porous polyethylene using twin wire-arc spraying.
• To evaluate the adhesion, morphology, and electrical properties of metallic coatings on porous PE.

Main Methods:

• Twin wire-arc spraying of copper (Cu), aluminum (Al), and zinc (Zn) onto 3 mm thick porous polyethylene substrates.
• Scanning electron microscopy (SEM) for surface and cross-section analysis.
• Adhesion strength and electrical resistivity testing.

Main Results:

• Successful deposition of ~400 µm thick metallic coatings (Cu, Al, Zn) without surface preparation.
• Observed differences in metal splat morphology and bonding mechanisms on porous vs. non-porous substrates.
• Coating bond strength exceeded the fracture strength of the porous polyethylene substrate.

Conclusions:

• Porosity in polyethylene substrates significantly enhances metallic coating adhesion.
• Twin wire-arc spraying is a viable method for metallizing porous polyethylene.
• This technique enables the creation of lightweight composite materials for thermal management applications.