Atomic Hydrogen Welding Overview

atomic hydrogen welding

Atomic Hydrogen Welding or Atomic Hydrogen Arc Welding is a welding technique that uses an arc between two tungsten electrodes in the presence of hydrogen gas. The electric arc formed between the two electrodes breaks the hydrogen molecules, which later react together to recombine. As a result, the process of recombination releases a high amount of heat, i.e. 3400-4000°C, and helps in the welding process. The Atomic Hydrogen Welding process was invented by Irving Langmuir in the early 20th century. Another name for the process is arc-atom welding.

Post Highlights:

  • Atomic Hydrogen Welding Meaning
  • Principle or How Does it Work?
  • AHW Features
  • Equipment Used
  • AHW Applications
  • Advantages
  • Disadvantages
  • Atomic Hydrogen Welder Salary

What is Atomic Hydrogen Welding?

Atomic Hydrogen Welding is a welding process that uses an arc between two tungsten electrodes in the presence of hydrogen gas. The arc formed between two wires breaks the hydrogen molecules, which later combines with a release of heat. This heat will increase the temperature to 3400-4000°C. This high amount of heat energy is used for welding purposes. In this process, a filler rod is optional.

AHW Principle

AHW is a welding process that uses an arc between two tungsten electrodes in the presence of hydrogen gas. Further, arc generation occurs when two electrodes of tungsten are kept in contact with each other.

The temperature of about 6000°C near the arc formed between two tungsten rods breaks the hydrogen molecules into hydrogen ions.

H2 2H

These hydrogen atoms will recombine together to form hydrogen molecules as soon as they come in contact with the relatively cooler surface with a high amount of release of heat.

2H H2+ heat

This heat will increase the temperature to 3400-4000°C, which is sufficient to melt the welding rod or filling rod.

To make the process successful, the welders should set up the following parameters. They are speed of travel, current setting, size of the arc, and contact of the arc with the work.

Atomic Hydrogen Welding Features

  • 4000º C is the average temperature of the flame produced.
  • The di-cyanoacetylene flame temperature is 4987º C and that of the cyanogen flame is 4525º C.
  • The passing of hydrogen gas through the tungsten electrodes increases electrode life.

Equipment Used in AHW

Atomic hydrogen arc welding uses the following basic equipment-


1. Tungsten Electrodes
The two tungsten electrodes are used in this technique. These electrodes are joined in a V-shape such that a gap of 1.5mm to 2mm is maintained at the tip of the two electrodes. The arc is produced between the two electrodes which help in welding.

2. Hydrogen Gas Cylinder
A hydrogen gas cylinder is required for this process. Also, as the process name suggests (Atomic Hydrogen Welding). Hydrogen gas is an essential factor in the welding process.

3. Filler Rod
The filler rod is optional in the atomic hydrogen welding process. It depends on the workpiece if a filler rod is required for welding or not.

4. Electrode Holder
The process requires two electrode holders. These electrode holders hold the tungsten electrodes and also prevent them from coming in direct contact with the hands of a welder.

5. Nozzles
During the process, two nozzles are connected to the electrode holders. Besides this, they supply an ample amount of hydrogen to surround the tungsten electrodes.

6. Pressure Regulator
A pressure regulator is a valve on the hydrogen gas cylinder. It works to measure the pressure of hydrogen gas and display it on the meter connected to it. The pressure regulator maintains a sufficient amount of hydrogen gas near the electrodes.

7. Transformer
A transformer of open-circuit voltage of 300 V is required. It helps to produce an arc between two tungsten electrodes and maintains it.

8. AC Power Supply
The main aim of using the AC power supply device is to maintain the voltage of 300V. The controller is also required to regulate the value of current as per the requirement. This power supply produces an arc between two tungsten electrodes.

Alternating Current (AC) is preferred instead of Direct Current (DC). It needs due to equal power is required in both the tungsten electrodes to make an arc between them.

Atomic Hydrogen Welding Applications

  1. The process can weld thin sheets of metals and small diameter alloys.
  2. The atomic hydrogen welding process is a suitable option for alloys like stainless steel where rapid welding is required.
  3. AHW type can be used to weld most of the metals whether they are iron, steel, and other metals and alloys.
  4. The process is employed to repair hard surfacing, joining parts, tools, and dies.

AHW Advantages

  1. The hydrogen gas which surrounds the electrodes also acts as a shielding gas and further prevents oxidation.
  2. It is one of the fastest techniques of welding types.
  3. The welders can easily concentrate the flame of the torch on the welding area.
  4. The hydrogen gas presented near tungsten electrodes prevents it from excessive heating. It ultimately increases the life of electrodes.
  5. The welding of alloys can be easily done without oxidation due to the reducing action of hydrogen.
  6. The process does not need things like striking the arc and maintaining the arc column as the workpiece does not form a part of the electric circuit.

Atomic Hydrogen Welding Disadvantages

  1. This process is not cost-effective as compared to other welding techniques available.
  2. The welding process is only effective on flat positions.
  3. It might be dangerous because the hydrogen gas used in this process is highly inflammable gas.
  4. The process requires a highly skilled person as it includes some technical aspects for performing.
  5. It is not a good option for depositing large quantities of metals.

Atomic Hydrogen Welder Salary

All the welders are not able to make the same amount of money. The salary depends on various factors such as educational level (programs), work skills, certification, working experiences, etc. As a worker gains experience the salary also increases. The salary depends on the kind of work a person is doing. Normally, an atomic hydrogen welder makes between $17 to $59 per hour. On average, they earn $32 per hour. Also, their average earnings are ranging from $50,630 and $67,087.


Atomic Hydrogen Welding is still in due to its properties despite being 100 years old. But the trends are changing in the new world of technology. Most of the works of atomic hydrogen welding are replacing by the MIG welding process. Whatever, atomic hydrogen welding deserves an important place in the welding industry. Thus, aspiring peoples can use the above information for study purposes and while working on the jobs.

Related: Other Welding Types

6 thoughts on “Atomic Hydrogen Welding Overview”

  1. Pingback: EZIIL

  2. Pingback: EZIIL

Leave a Reply

Scroll to Top
Welding Machine Types Welding Procedure Specification AWS Welding Certifications AWS D1.1:2020 Changes Welding Joint Types DCEN and DCEP Polarity