What are the differences between tungsten electrodes and molybdenum electrodes?

2025,12,27

Tungsten electrodes and molybdenum electrodes are both high-performance refractory metal electrodes, widely used in welding, metallurgy, electronics, and other industrial fields, but they differ significantly in material properties, application scenarios, performance advantages, and limitations. The detailed differences are as follows:

Comparision dimensions	Tungsten electrode	Molybdenum Electrodes
Core Material Properties	1. Ultra-high melting point 3422 ℃, the highest among pure metals2. High density (19.3 g/cm³), good rigidity3. Strong arc stability, low vapor pressure at high temperature4. Brittle at room temperature, easy to break when impacted	1. High melting point 2620℃, lower than tungsten but still excellent2. Moderate density (10.28 g/cm³), lighter than tungsten3. Good ductility at room temperature, easy to process into various shapes4. High thermal conductivity and electrical conductivity, close to copper
Main Types & Modifications	Often doped with rare earth oxides (e.g., ThO₂, CeO₂, La₂O₃) to improve arc ignition performance and service life, divided into WT20, WC20, WL15 and other grades	Mostly pure molybdenum or molybdenum alloys (e.g., Mo-La alloy, Mo-Ti alloy) to enhance high-temperature strength and oxidation resistance
Key Application Scenarios	1.TIG welding(tungsten inertgas welding The most core application, used for welding stainless steel, aluminum alloy, titanium alloy and other precision components2. Plasma cutting/arc spraying: As arc electrodes to generate stable high-temperature plasma arcs3. Semiconductor industry: Used for high-temperature heating electrodes in crystal growth furnaces	1. Vacuum metallurgy: As heating electrodes in vacuum furnaces, used for smelting high-temperature alloys, rare metals2. Glass manufacturing: Used for electrodes in glass melting furnaces (resistant to glass corrosion)3. Electrochemical industry: Used for electrodes in electrolysis of molten salts, electroplating4. Lighting industry: As support electrodes for incandescent lamp filaments
High-temperature Performance	Excellent high-temperature stability, can work stably under 2000~3000℃ in inert atmosphere; easy to oxidize in air above 400℃, forming volatile WO₃	Good high-temperature strength, but oxidation resistance is worse than tungsten; oxidizes rapidly in air above 600℃, forming MoO₃ which volatilizes easily; needs protection in vacuum or inert gas
Processing Characteristics	Brittle at room temperature, difficult to process (needs hot forging, wire drawing at high temperature); easy to break during mechanical operation	Good room-temperature ductility, easy to process into sheets, wires, rods; low processing cost compared with tungsten
Cost & Availability	Tungsten ore resources are relatively scarce, and the preparation process of doped electrodes is complex, so the cost is higher	Molybdenum ore resources are more abundant, and the processing technology is mature, so the cost is lower is than tungsten electrodes
Limitations	1. Poor room-temperature toughness, easy to crack under impact2. High cost limits large-scale application3. Oxidation failure is easy in air at high temperature	1. Lower melting point than tungsten, cannot be used in ultra-high temperature environments above 2600℃2. Poor oxidation resistance, must be used in protective atmosphere

Summary of Core Selection Principles

Choose tungsten electrodes when you need ultra-high temperature resistance, stable arc performance, such as precision TIG welding, plasma arc applications, and semiconductor high-temperature processes.

Choose molybdenum electrodes when you need good processability, low cost, and work in vacuum/inert gas environments below 2600℃, such as vacuum furnace heating, glass melting, and electrochemical electrolysis.

Author:

Mr. zengzheng

E-mail:

zzjd@chinatungstenalloy.com

Phone/WhatsApp:

+86 18973369812