Helium's high ionization potential creates a hotter, more energetic arc that increases heat input by 25-40% compared to pure argon, making it essential for thick aluminum and high-thermal-conductivity materials. This extra energy overcomes heat sink effects that would otherwise prevent proper fusion.
Helium: Heat Input Boost and Penetration Improvement
How Helium Increases Heat Input
- Higher ionization energy required. Helium needs more energy to ionize, creating a hotter arc column.
- Increased arc voltage. Same current produces 2-3V higher arc voltage with helium content.
- Better heat transfer efficiency. Higher thermal conductivity moves heat into base metal faster.
- Wider arc cone. Helium creates broader heat distribution for better fusion on thick materials.
When Helium Additions Pay Off
- Thick aluminum (>6mm). Overcomes aluminum's high thermal conductivity.
- Copper and copper alloys. Essential for achieving fusion in high-conductivity metals.
- High-speed welding. Maintains penetration at faster travel speeds.
- Out-of-position welding. Higher heat input improves tie-in on vertical and overhead welds.
Helium Percentage Guidelines
25-30% He: Moderate heat increase, good for 6-12mm aluminum, maintains arc stability.
50% He: Significant heat boost for thick sections (12-25mm), industry standard for production.
70-75% He: Maximum practical helium content, for very thick materials or high-speed automation.
Pure helium: Rarely used due to arc instability and gas cost, specialized applications only.
Premium Performance
VARIGONĀ® He50
50% Ar / 50% HeWhy 50% helium is optimal: Provides substantial heat input increase (35% more than pure argon) while maintaining good arc stability and reasonable gas costs.
Best applications for He50: Thick aluminum fabrication, copper welding, high-speed production lines, and any situation requiring maximum penetration.
š„ High Heat Process