TIG (GTAW)

TIG (GTAW) creates high-quality fusion welds with a non-consumable tungsten electrode and shielding gas, offering precise heat control and clean finishes.

Overview

TIG (GTAW), also called TIG or heliarc welding, is an arc welding process that uses a non-consumable tungsten electrode and inert shielding gas (typically argon) to produce a fusion weld. Filler metal is added separately as needed, which gives the welder tight control over bead size, heat input, and puddle placement.

Choose TIG when weld quality, appearance, and metallurgical control matter more than speed—thin wall parts, leak-tight joints, and reactive or crack-sensitive materials are common drivers. It works well on stainless, aluminum, titanium, and nickel alloys, and supports out-of-position and intricate joints when access is available.

Tradeoffs: deposition rate is low and labor is high, so cost scales quickly with weld length. Joint fit-up and cleanliness heavily affect results, and aluminum often needs AC TIG and good oxide removal. Wind and poor gas coverage cause porosity, so fixturing and shielding discipline matter.

Common Materials

  • Stainless steel 304
  • Stainless steel 316
  • Aluminum 6061
  • Titanium Grade 2
  • Inconel 625
  • Carbon steel 1018

Tolerances

±0.010"

Applications

  • Stainless sanitary tubing welds
  • Aluminum intercooler and charge piping
  • Pressure vessel nozzles and small manifolds
  • Thin-wall sheet metal enclosures and brackets
  • Titanium exhaust and aerospace ducting
  • Hydraulic and instrument tubing assemblies

When to Choose TIG (GTAW)

TIG is a strong fit for low to medium volumes where weld integrity, cosmetics, and heat control are critical, especially on thin sections. It’s well-suited to parts that need leak-tight seams, minimal spatter, and controlled distortion with accessible joints and good fit-up.

vs MIG (GMAW)

Choose TIG over MIG when you need tighter heat control, cleaner beads with minimal spatter, and better results on thin material or cosmetic surfaces. TIG is also preferred when procedure control and weld quality requirements dominate over throughput.

vs Stick (SMAW)

Choose TIG over stick when weld appearance, low spatter, and precise control on thin or small features matter. TIG performs better for shop-built assemblies with clean base metal and where access allows a steady torch angle and gas shielding.

vs Resistance Welding

Choose TIG over resistance welding when you’re not joining lap joints of thin sheet, when the weld path isn’t a simple spot/seam pattern, or when you need full-penetration butt/fillet welds on thicker sections. TIG also fits prototypes and mixed-joint geometries without dedicated electrode tooling.

vs Laser Welding

Choose TIG over laser welding when joint gaps vary, fit-up isn’t production-tight, or you need manual adaptability around complex assemblies. TIG is typically easier to qualify and repair in general job-shop environments, especially for short-run work.

vs Brazing & Soldering

Choose TIG over brazing/soldering when you need a true fusion joint with base-metal strength, higher temperature capability, and better pressure/leak performance. TIG is also preferred when joint cleanliness and long-term corrosion behavior under load are critical.

Design Considerations

  • Specify base material grade and filler metal requirements (or allow shop selection) to avoid rework and qualification delays
  • Call out joint type and weld size clearly (fillet leg size, throat, or full-penetration) and define whether cosmetic blending is required
  • Design for torch and cup access; tight corners and deep pockets drive custom torches, poor shielding, and higher scrap risk
  • Control fit-up with realistic gap tolerances and edge prep notes; inconsistent gaps increase heat input, distortion, and porosity
  • Minimize long continuous weld lengths on thin parts or include distortion control features (stitch welds, tabs, fixturing datums)
  • For aluminum and titanium, include surface prep and shielding requirements (oxide removal, purge/backing gas) if leak-tight or high-integrity welds are needed