Machining Argon Arc Welding
Customized according to drawings and quantities
Technical principles and core advantages
Technical basis: Argon (Ar) is used as the shielding gas. The base material and welding wire are heated through a tungsten electrode (TIG) or a melting electrode (MIG) arc to form a molten pool and then cooled to crystallize. The high inertness of argon effectively isolates oxygen and nitrogen, preventing oxidation of the weld seam and ensuring the purity of the weld metal. For instance, the corrosion resistance of the 316L stainless steel argon arc welded weld seam can rival that of the base material, making it suitable for offshore platforms and chemical equipment.
Core advantages
Precision: Controllable heat input, narrow heat-affected zone (HAZ) (≤0.5mm), suitable for thin-walled parts (starting from 0.5mm) and complex structure welding, such as medical implants and precision instrument casings.
Stable quality: The weld formation is aesthetically pleasing (with uniform fish-scale patterns), and the defect rate is low (porosity and crack probability < 0.1%), meeting the requirements of high reliability.
Wide material compatibility: Compatible with stainless steel, titanium alloy, aluminum alloy, nickel-based alloy, etc., especially suitable for welding dissimilar metals (such as steel-aluminum transition joints).
Environmental friendliness: No smoke or dust, low splashing, suitable for clean workshops (such as semiconductor and food processing equipment production).
Customized requirements and process parameters
Material selection
Stainless steel: 304/316L (corrosion-resistant), duplex steel (high strength) Surface treatment should be matched with welding (such as pickling and passivation to remove the oxide layer).
Titanium alloy: It has excellent biocompatibility and is used in medical implants (such as artificial joints), where hydrogen content needs to be controlled to prevent cold cracking.
Aluminum alloy: Preheating (100-200℃) is required to prevent hot cracking, and AC TIG or pulse MIG processes should be adopted.
Parameter optimization
Current/Voltage: When welding stainless steel with DC TIG, the current is 50-300A (adjusted according to the plate thickness), and the voltage is 10-20V. Pulse MIG can refine grains and enhance the toughness of weld seams.
Welding speed: 0.1-1m/min. It should be balanced with the heat input to avoid burn-through or incomplete fusion.
Protective gas: Pure argon (99.99%) or argon + helium mixture (to enhance arc stability), flow rate 5-20L/min.
Tungsten electrode selection: Cerium tungsten electrode (CeO₂) is suitable for DC welding, while lanthanum tungsten electrode (La₂O₃) is heat-resistant and suitable for high-current scenarios.
Structural design: Reduce welding deformation through topological optimization. Use "fixture + positioning pin" to ensure clamping accuracy (repeat positioning accuracy ±0.05mm), suitable for curved surfaces and thin-walled structures.
Process flow and quality control
Process flow
Design stage: CAD modeling, weld path planning, and optimization of welding sequence (such as symmetrical welding to reduce deformation).
Preparation stage: Material cutting (laser/water jet), surface treatment (rust removal/oxide layer removal), fixture installation (hydraulic/pneumatic clamping).
Welding stage: The robot/manual TIG performs welding, with real-time monitoring of current/voltage and dynamic adjustment of parameters.
Post-treatment: Weld seam cleaning (removal of slag), heat treatment (annealing/aging), surface polishing (mirror effect), non-destructive testing (X-ray/ultrasonic).
Quality control
Online detection: The vision system detects the position/width of the weld seam, the arc sensor monitors the penetration depth, and the laser displacement sensor measures the height of the weld seam.
Offline inspection: X-ray flaw detection (for internal defect detection), ultrasonic testing (weld thickness), hardness testing (HV), metallographic analysis (grain structure).
The standards comply with: ISO 15614 (Welding Procedure Qualification), ASTM E1417 (Non-destructive Testing), ISO 13485 (Medical Equipment), ASME BPVC (Pressure Vessels).
Application scenarios and cases
Medical devices: Surgical instruments (such as bone forceps), implants (artificial joints, heart stents), biocompatible sealing achieved through argon arc welding, meeting ISO 13485 certification.
Aerospace: Engine blades (titanium alloy TIG welding), fuel pipelines (electron beam welding + argon gas protection), resistant to high temperature and high pressure (above 300℃) and vibration environments.
Automobile manufacturing: Exhaust system (stainless steel TIG welding), battery pack aluminum housing (MIG welding), enhancing structural strength and sealing performance.
Energy equipment: Nuclear power plant pressure vessels (thick plate welding), oil and gas pipelines (automatic welding machine + argon gas protection), compatible with IP68/IP69K protection grades.
Construction and pipelines: Steel structure Bridges (thick plate welding), urban pipe networks (stainless steel pipes), enhancing construction efficiency and corrosion resistance.
