Welding Guidelines for Inconel Alloys – Crack-Free Results (Complete 2025 Guide)

Inconel’s microstructure and nickel-rich chemistry make it strong, but difficult to weld.

High solidification range increases chances of solidification cracking.

Causes distortion and weld stress.

Requires careful machining and preparation.

Needs excellent shielding gas coverage.

Heat must be controlled to prevent cracking or strength loss.

• Excellent control
• Best for thin to medium thickness
• Ideal for high-quality welds
• Suitable for Inconel 625, 600, 718

• Faster deposition
• Good for thicker sections
• Requires Ar + He gas mix

• Good for field repairs
• Uses ENiCrFe electrodes

• High precision
• Used in aerospace

• Low heat input
• Best for high-value precision components

• ERNiCrMo-3 (Inconel 625 filler)
• ENiCrMo-3 (SMAW)

• ERNiFeCr-2
• ERNiCr-3 (dissimilar welds)

718 requires post-weld heat treatment (PWHT).

• ERNiCr-3

• ERNiCr-3
• ERNiCrMo-3 (for corrosion service)

• Remove oil, grease, dirt, oxides, moisture

• 37.5° V-groove
• 60° U-groove

For very thick sections (especially 718): 100–200°C.

Prevents grain growth and cracking. Pulsed TIG recommended.

• TIG Current: 70–150 A
• Voltage: 10–14 V
• Shield Gas: Argon 99.99%
• Flow Rate: 15–20 LPM
• For thicker welds, use Argon + Helium

• Use low heat input
• Control cooling rate
• Use correct filler metal
• Avoid sulfur-contaminated materials
• Use stringer beads, not weave beads
• Maintain interpass temp below 120°C

• Excellent weldability
• Use ERNiCrMo-3
• No PWHT required
• Good for seawater & chemical systems

• Requires PWHT (980–1000°C + aging)
• Use pulsed TIG
• Use ERNiFeCr-2 filler

• Use ERNiCr-3
• Keep interpass temp low

• Use lower heat to avoid grain growth
• ERNiCr-3 recommended

• Inconel 625: No PWHT required
• Inconel 718: Must undergo solution + aging treatment
• Inconel 600, 800, 825: Optional based on service conditions

• Hot Cracking: Use correct filler, low heat
• Porosity: Clean metal, use pure argon
• Lack of Fusion: Use stringer beads, increase travel speed
• Oxidation: Improve shielding gas coverage
• Warping: Use fixtures, low heat input