Matweld Welding Rods Alum Arc 2.5mm M009

The Matweld M009 is a specialized aluminum arc welding electrode designed for maintenance and repair work using a standard DC welding machine. These electrodes feature a high-quality extruded flux coating that acts as a cleaning agent, shielding gas, and slag-former, allowing for the welding of aluminum and aluminum alloys without the need for a TIG or MIG setup.

Technical Specifications

• Electrode Diameter: 2.5mm.
• Product Code: MAT3340 (Typical for the 1kg or 2kg pack).
• Alloy Type: Aluminum-Silicon (typically AlSi12 or AlSi5).
• Welding Current: DC+ (Electrode Positive).
• Amperage Range: 60A – 90A (Recommended for 2.5mm).
• Tensile Strength: Approximately 180 MPa

Key Features

• Versatile Repair Tool: Ideal for repairing cracks in aluminum castings, engine blocks, cylinder heads, and aluminum tanks where a portable Stick (MMA) welder is the only tool available.
• Excellent Fluxing Action: The coating contains aggressive chemicals that break down the stubborn aluminum oxide layer, ensuring a solid metallurgical bond.
• Rapid Freezing Slag: The slag solidifies quickly, making it easier to control the weld pool, which is notoriously fluid and difficult to manage compared to steel.
• Corrosion Resistance: The weld deposit provides good resistance to environmental corrosion and matches the color of most common aluminum alloys well.

Common Applications

• Automotive: Repairing cracked sumps, gearbox housings, and aluminum radiator brackets.
• Agricultural: On-site repairs to irrigation pipes, aluminum ladders, and livestock trailers.
• Marine: Patching aluminum hulls and repairing salt-corroded marine fittings.
• Industrial: Joining aluminum busbars and maintaining ventilation ducting.

Critical Usage & Maintenance Tips

• Strict Storage: Aluminum electrodes are highly hygroscopic (they suck moisture out of the air). If the flux becomes damp, the arc will be unstable and cause porosity. Always keep them in a sealed, dry container or an electrode oven.
• Surface Preparation: Unlike steel, aluminum must be perfectly clean. Use a stainless steel wire brush (used only for aluminum) to scrub the joint until it is shiny. Wipe with a solvent if any oil or grease is present.
• Pre-Heating: For aluminum thicker than 3mm, it is highly recommended to pre-heat the workpiece to approximately 150°C – 200°C. This prevents "cold-start" defects and ensures better penetration.
• Technique: Use a short arc and a fast travel speed. Aluminum conducts heat very quickly, so the "melt-through" risk is much higher than with steel.
• Slag Removal: The flux residue is corrosive. You must chip away the slag and wash the weld area with warm water and a brush once the metal has cooled to prevent long-term pitting.