Welding All Information

What is Welding?
Welding is a fabrication process that lets you join materials like metals by using heat at high
temperatures. Welding uses high temperatures to join the materials, whereas soldering and
brazing do not allow the base metal to melt. After cooling, the base metal and the filler metal
get attached.
The welding process came to light when there was a search for a technique for developing iron
into useful shapes. Welded blades were the first result of welding in the early years—the
carburization of iron produced hard steel that was very brittle for usage. Later interlaying the
rigid and soft iron with high-carbon material and hammer forging resulted in a tough and
durable blade.
The process of welding uses filler material. The filler material is the pool of molten material that
aids in the formation of a strong link between the base metal. The shielding process after
welding the metals protects both the base and filler components from being oxidized. From gas
flame to ultrasound, many energies are used in welding like electron beams, electric arc, LASER,
and friction. Now let us understand various types of welding.

Types of Welding
There are many types of welding used for various purposes in different situations. They are:
Manual welding includes:
 Forge welding
 Arc welding
 Oxy-fuel welding
 Shielded metal arc welding
 Gas metal arc welding
 submerged arc welding
 flux-cored arc welding
 electro slag welding
 Laser beam welding
 electron beam welding
 magnetic pulse welding
 friction stir welding
Forge Welding
Forge welding is the early version of welding which was used to join the small iron pieces to
make larger valuable pieces. It is the simplest welding method where two metals are heated
and joined and later hammered for the finishing purpose.
Arc Welding
Arc welding is the most common type of welding seen today. Arc welding is a type of welding in
which an electric arc is created to heat and join metals. Tiny globules of molten metal are
transferred from the metal electrode to the weld joint.
Oxy-Fuel Welding
Oxy-fuel welding is oxy welding, gas welding, or oxy-acetylene welding. This process uses the
combustion of fuel gases like acetylene and oxygen to weld or cut the metals. Edmond Fouché
and Charles Picard, French engineers in 1903, developed Oxy-fuel welding.
When acetylene and oxygen are mixed in proper measures inside the hand-held torch or
blowpipe, the hot flame is produced in the hand-held torch measuring 3,200 degrees Celsius.
The flame’s intensity can be manipulated by altering the proportion of the volume of oxygen to
acetylene. Welding can be done using this flame.
Shielded Metal Arc Welding
Various names like flux shielded arc welding, manual metal arc welding, or stick welding are
known as shielded metal arc welding. It is a manual welding process that uses an electrode
covered with flux to perform welding.
AC or DC power supply forms an electric arc between the electrode and the metals to be joined.
Gas Metal Arc Welding
Gas metal arc welding in which an electric arc is formed between a consumable metal inert gas
wire electrode and the workpiece metal. The generated heat melts the workpiece metal and is
then joined. It is a semi-automatic or automatic process that uses AC or DC from the power
supply.
Submerged Arc Welding
Submerged arc welding is a type of arc welding process that involves forming an arc between
the electrode and the workpiece. A blanket of granular fusible material shields the arc on the
work.
Flux-Cored Arc Welding
Flux-cored arc welding is a semi-automatic or automatic arc welding process. Flux-cored arc
welding is similar to the metal-active gas welding process. It uses a continuous wire-fed
electrode and a constant-voltage welding power supply.
Electroslag Welding
Electroslag welding is the most effective welding used to weld materials more significant than
25 mm up to about 300 mm. In electro-slag welding, heat is generated by passing electricity
between the filler metal and the workpiece through a molten slag covering the weld surface.
Laser Beam Welding
Laser beam welding is the process in which metal or thermoplastic materials are joined
together with the aid of LASER (Light Amplification by Stimulated Emission of Radiation). It is an
efficient technique that can perform deep welds. Laser beam welding is a non-contact process
requiring access to the weld zone from one side of the welded parts. Since the LASER beam is
monochromatic and single-phased, without any divergence, high energy light produced is
channelized to perform welding.
Electron Beam Welding
Electron beam welding is a technique in which high-velocity electrons are applied to the
materials to be welded. Electron beam welding is undertaken under vacuum conditions to
prevent dissipation of the electron beam. The kinetic energy from the electrons is transformed
into heat, and the materials are welded. The electron gun is used to generate electrons, and the
electron gun helps control the flow of the electrons. Electron beam welding is performed in a
vacuum condition to avoid the scattering of electrons.
Magnetic Pulse Welding
Magnetic pulse welding is a technique that uses magnetic force to weld two materials together.
It is the solid-state welding developed in 1970 and is used extensively in automotive industries.
It is the fastest way of welding, which consumes only microseconds without the need for
welding consumables or shielding gases.
Friction Stir Welding
Friction stir welding is also a solid-state welding process that uses frictional heat generated by a
rotating tool to join materials.
The tool, equipped with a profiled probe and shoulder, is rotated and plunged into the interface
between two workpieces. The tool, when moved along the joint line, causes the material to
heat and soften. The shoulder also acts to contain this plasticized material, which is
mechanically mixed to create a solid phase weld.
Advantages and Disadvantages of Welding
Advantages
 Welding establishes strong, durable, and permanent joint links.
 It is a simple process that results in a great finish.
 The technique, when used with filler material, produces a stronger weld than the base
material.
 It can be performed at any place
 It is an economical and affordable process
 It is used in various sectors like construction, automobile, and many more industries.
Disadvantages
 It is hazardous when performed under the safety and security guidelines.
 It is a difficult task to dismantle the joined material through welding.
 Requires skilled labor and electric supply.

MMA welding position classifications

MMA (Manual Metal Arc) welding, also known as shielded metal arc welding (SMAW), can be
performed in several positions. Here are the main welding positions:
1. Flat Position (1G): The workpiece is horizontal, and the welder can access it easily. This is the
most common position and usually the easiest.
2. Horizontal Position (2G): The workpiece is vertical, but the weld is made on a horizontal
surface. The welder may have to work at an angle.
3. Vertical Position (3G): The workpiece is positioned vertically, and the weld is made from the
bottom to the top. This position is more challenging due to the effects of gravity on the molten
metal.
4. Overhead Position (4G): The workpiece is overhead, and the welder must work from below.
This position is difficult and requires good technique to prevent slag and molten metal from
falling.
5. Pipe Position (5G/6G): Welding on a pipe can be done in multiple positions, with 5G being
horizontal and 6G at a 45-degree angle. This position is common in pipeline welding and is
technically challenging.
Each position presents unique challenges and requires different skills and techniques for
effective welding.
What is CCWM and CVWN?
CCWM and CVWN refer to specific welding processes:
1. CCWM (Constant Current Welding Machine): This type of welding machine maintains a
constant current during the welding process. It's commonly used for processes like MMA
(SMAW) and TIG welding. The constant current helps achieve consistent penetration and
control over the weld pool, which is essential for producing quality welds.
2. CVWN (Constant Voltage Welding Machine): This machine maintains a constant voltage
while the current may vary. It's typically used for processes like MIG (GMAW) welding. The
constant voltage setting helps maintain a stable arc length, making it easier to achieve
consistent weld quality, especially in automated or semi-automated settings.
Both types of machines are crucial in different welding applications, offering specific advantages
based on the requirements of the weld.

why use flux as a coating in welding electrodes?

Flux coating on welding electrodes serves several important purposes:
1. Protection from Contamination: The flux creates a shielding gas when heated, which
protects the molten weld pool from atmospheric gases, such as oxygen and nitrogen. This
prevents oxidation and contamination of the weld.
2. Stabilizing the Arc: Flux helps to stabilize the welding arc, making it easier to maintain a
consistent and controlled arc length. This results in smoother and more uniform welds.
3. Slag Formation: As the flux melts, it forms a layer of slag on top of the weld bead. This slag
protects the cooling weld from atmospheric exposure and can help with the removal of
impurities from the molten metal.
4. Improving Weld Properties: Different flux compositions can enhance the mechanical
properties of the weld, such as its strength and ductility. Some fluxes can also improve the
appearance of the weld.
5. Ease of Cleanup: The slag produced by the flux can be easily removed after the weld cools,
leaving a clean weld surface.
Using flux-coated electrodes is essential for producing high-quality welds in various welding
processes, particularly in environments where contamination is a concern.
ACM gas mixtures
ACM (Argon-Carbon Dioxide-Mixed) gas mixtures are commonly used in MIG (Metal Inert Gas)
welding, particularly for welding carbon steels. Here’s a breakdown of ACM gas mixtures:
1. Argon (Ar): An inert gas that provides a stable arc and enhances weld quality. It helps to
stabilize the welding process and minimizes spatter.
2. Carbon Dioxide (CO₂): A reactive gas that improves the arc characteristics and increases
penetration. CO₂ is less expensive than argon, making it a popular choice for various
applications.
Common Mixtures:
-Argon 75% - CO₂ 25%: A widely used mixture that offers good arc stability and penetration. It’s
suitable for welding thin to medium-thick materials.
-Argon 80% - CO₂ 20%: This blend offers a balance between penetration and spatter control,
making it effective for many welding applications.
-Argon 90% - CO₂ 10%: Used for applications requiring a smoother weld appearance with less
spatter.
Benefits of ACM Mixtures:
-Improved Weld Quality: The combination provides better arc stability and reduced spatter,
resulting in cleaner welds.
-Versatility: Suitable for a range of materials and thicknesses.
-Cost-Effectiveness: CO₂ is generally less expensive than argon, making these mixtures more
economical for large-scale operations.
Applications:
ACM gas mixtures are often used in:
- Automotive repair and manufacturing
- General Fabrication
- Structural steel welding
Overall, ACM gas mixtures are favored for their ability to balance cost, performance, and weld
quality in various welding applications.

what are general fabrications?

General fabrication refers to the process of creating structures, components, or assemblies
from raw materials, typically metal or plastic, through various manufacturing techniques. It
encompasses a wide range of activities and can include:
Key Aspects of General Fabrication:
1. Cutting: Using tools like saws, plasma cutters, or lasers to shape materials into required
dimensions.
2. Forming: Altering the shape of materials through processes such as bending, rolling, or
stamping.
3. Welding: Joining materials together using techniques like MIG, TIG, or arc welding.
4. Machining: Using machines to remove material and achieve precise dimensions, often
through processes like milling or drilling.
5. Finishing: Applying surface treatments to enhance appearance or durability, such as painting,
coating, or polishing.
Applications:
General fabrication is used in various industries, including:
- Construction: Creating structural components for buildings and infrastructure.
- Automotive: Manufacturing parts for vehicles.
- Manufacturing: Producing equipment, machinery, and tools.
- Shipbuilding: Fabricating parts for vessels and marine structures.
- HVAC: Making ductwork and other components for heating, ventilation, and air conditioning
systems.
Importance:
General fabrication is crucial for producing custom parts and products tailored to specific
needs. It plays a significant role in innovation, allowing for the development of new designs and
solutions across multiple sectors.
ACM 2,10,15,18,20,25,30 gas mixtures ratio
The ACM (Argon-Carbon Dioxide-Mixed) gas mixtures you mentioned refer to specific ratios of
argon (Ar) and carbon dioxide (CO₂) used in MIG (Metal Inert Gas) welding. Here's a breakdown
of each mixture:
ACM Gas Mixtures:
1. ACM 2 (Argon 2% - CO₂ 98%):
- Very high CO₂ content, typically used for specific applications that require deep penetration
and are less concerned about spatter.
2. ACM 10 (Argon 10% - CO₂ 90%):
- Provides a balance between penetration and spatter control, suitable for general welding of
carbon steels.
3. ACM 15 (Argon 15% - CO₂ 85%):
- Offers improved arc stability and reduced spatter compared to higher CO₂ mixtures, making
it versatile for various applications.
4. ACM 18 (Argon 18% - CO₂ 82%):
- A good choice for both thin and thick materials, balancing penetration and weld quality.
5. ACM 20 (Argon 20% - CO₂ 80%):
- This mixture enhances arc stability while still providing good penetration, making it effective
for a wide range of welding tasks.
6. ACM 25 (Argon 25% - CO₂ 75%):
- Offers excellent arc stability and less spatter, ideal for applications where a clean weld
appearance is important.
7. ACM 30 (Argon 30% - CO₂ 70%):
- High argon content enhances the quality of the weld, suitable for critical applications where
aesthetics and strength are vital.
Summary:
Each of these mixtures serves different purposes based on the specific needs of the welding
application, such as material thickness, desired penetration, and aesthetic considerations. The
choice of gas mixture can significantly influence the quality and characteristics of the weld.
Here are the specific gas mixture ratios for ACM (Argon-Carbon Dioxide-Mixed) gas mixtures:
1. ACM 2: Argon 2% - CO₂ 98%
2. ACM 10: Argon 10% - CO₂ 90%
3. ACM 15: Argon 15% - CO₂ 85%
4. ACM 18: Argon 18% - CO₂ 82%
5. ACM 20: Argon 20% - CO₂ 80%
6. ACM 25: Argon 25% - CO₂ 75%
7. ACM 30: Argon 30% - CO₂ 70%

Summary of Applications:
Low Argon Content (e.g., ACM 2, 10): Higher CO₂, good for deep penetration, but may have
more spatter.
Medium Argon Content (e.g., ACM 15, 18, 20): Balanced penetration and arc stability,
versatile for various applications.
High Argon Content (e.g., ACM 25, 30): Better arc stability and reduced spatter, ideal for
cleaner welds and critical applications.
Choosing the right mixture depends on the specific welding requirements and desired
outcomes.

Benefits of using ACM in welding

Using ACM (Argon-Carbon Dioxide-Mixed) gas mixtures in welding offers several key benefits:
1. Enhanced Weld Quality
- Cleaner Welds: The shielding effect of the gas minimizes oxidation and contamination,
resulting in stronger and more aesthetically pleasing welds.
- Reduced Spatter: The combination of argon and CO₂ leads to less spatter, making cleanup
easier and improving the overall appearance of the weld.
2. Versatility
- Wide Range of Applications: ACM mixtures can effectively weld various materials, including
carbon steels, stainless steels, and some aluminum alloys, making them suitable for many
industrial applications.
3. Improved Penetration
- Deep Penetration: The CO₂ component provides excellent penetration, making ACM
mixtures ideal for welding thicker materials while maintaining control over the weld pool.
4. Stable Arc
- Ease of Use: The stable arc created by the gas mixture helps reduce the likelihood of arc
interruptions, making it easier for welders to maintain consistency and quality.
5. Cost-Effectiveness
- Lower Costs: CO₂ is generally less expensive than argon, which can reduce overall shielding
gas costs while still providing good performance.
6. Reduced Sensitivity to Contaminants
- Outdoor Use: ACM mixtures are less sensitive to surface contaminants compared to pure
argon, making them suitable for outdoor welding or less controlled environments.
7. Customizable Performance
- Tailored Ratios: Different ratios of argon to CO₂ allow welders to customize the gas mixture
based on specific application requirements, optimizing for factors such as penetration, heat
input, and spatter control.
8. Wider Operating Range
- Flexible Welding Conditions: ACM mixtures can accommodate various welding conditions,
including different positions and speeds, making them versatile for different projects.
Summary
Overall, ACM gas mixtures offer a balanced approach to MIG welding, combining quality,
versatility, and cost-effectiveness, which makes them a popular choice in many welding
applications.

What is TWY and KWS

TWY and KWS are terms commonly used in welding and metalworking contexts:
1. TWY (Tungsten Inert Gas Welding - TIG) Wires
- Tungsten Inert Gas Welding: While TWY isn’t a standard acronym, it often refers to TIG
welding processes involving tungsten electrodes. TIG welding is known for its precision and
ability to weld thin materials.
- Applications: Used in high-quality welding applications, such as aerospace, automotive, and
artistic metalwork.
2. KWS (KiloWatts)
- KiloWatts: This is a measure of electrical power. In welding, it can refer to the power output of
welding machines or systems. Knowing the KWS can help in determining the capability and
efficiency of the welding equipment.
- Applications: Important for calculating energy consumption, ensuring proper equipment
selection for specific welding tasks, and managing operational costs.

Welding defects
Welding defects can compromise the integrity and performance of a welded joint. Here are
some common types of welding defects:
1. Porosity
- Description: The presence of small holes or voids in the weld metal caused by trapped
gas.
- Causes: Contaminated base materials, moisture in the electrode, or improper shielding
gas.
2. Cracking
- Description: Cracks that can occur in the weld metal or heat-affected zone (HAZ).
- Causes: Rapid cooling, improper welding techniques, or excessive stress on the joint.
3. Incomplete Fusion
- Description: Failure of the weld metal to fuse completely with the base material.
- Causes: Insufficient heat, improper electrode angle, or contamination.
4. Undercut
- Description: A groove that forms along the edge of the base metal at the weld,
weakening the joint.
- Causes: Excessive heat input, fast travel speed, or improper technique.
5. Overlapping
- Description: Occurs when the weld metal does not penetrate fully and flows over the
base material instead.
- Causes: Incorrect angle or speed, low heat, or improper filler material.
6. Slag Inclusions
- Description: Non-metallic solid materials trapped in the weld, which can weaken the
joint.
- Causes: Improper cleaning, insufficient welding technique, or incorrect flux usage.
7. Misalignment
- Description: When the pieces being welded are not properly aligned, resulting in an
uneven or weak joint.
- Causes: Poor setup, improper clamping, or thermal expansion.
8. Excessive Reinforcement
- Description: An overly thick layer of weld metal that can create stress concentrations.
- Causes: Incorrect welding technique or excessive filler material.
9. Burn-Through
- Description: A hole or opening those forms in the base metal due to excessive heat.
- Causes: High heat input, improper material thickness, or excessive travel speed.
10. Heat Affected Zone (HAZ) Issues
- Description: Changes in the material properties of the base metal adjacent to the weld.
- Causes: Overheating, leading to brittleness or changes in microstructure.

Prevention and Control

To minimize welding defects, consider the following strategies:
 Proper Preparation: Clean the base material and ensure proper alignment.
 Control Heat Input: Use appropriate welding parameters and techniques.
 Use Quality Materials: Select suitable filler materials and shielding gases.
 Regular Inspections: Conduct visual and non-destructive testing (NDT) to detect defects
early.
Understanding and addressing these potential defects is crucial for ensuring the integrity and
durability of welded structures.

Porosity short arc length

Porosity in welding refers to the presence of small holes or voids in the weld metal, often
caused by trapped gases. A short arc length can contribute to porosity for several reasons:
Effects of Short Arc Length on Porosity:
1. Increased Heat:
- A short arc length generates more concentrated heat, which can lead to rapid melting and
gas expansion, trapping gas in the weld.
2. Inadequate Shielding:
- The close distance may not allow sufficient shielding gas coverage, increasing the likelihood
of atmospheric contamination.
3. Faster Solidification:
- The weld pool may solidify too quickly, not allowing trapped gases to escape, leading to
porosity.

Prevention:
To reduce porosity associated with short arc lengths, consider the following:
- Adjust Arc Length: Maintain an appropriate arc length for the specific welding process.
- Proper Technique: Use correct welding techniques and travel speed to control heat
input.
- Clean Materials: Ensure that the base materials are clean and free from contaminants.
- Shielding Gas: Use the appropriate shielding gas and flow rate to protect the weld pool.
By addressing these factors, the risk of porosity can be minimized, leading to higher-quality
welds.
Porosity in welding typically refers to the presence of small holes or voids in the weld metal
caused by trapped gases. While an air-free environment can help reduce porosity, it’s
important to understand how it relates to the overall welding process.

Air-Free Environment and Porosity

1. Reduced Atmospheric Contamination:
- An air-free environment minimizes the risk of atmospheric gases (like oxygen and nitrogen)
contaminating the weld pool, which can lead to porosity.
2. Controlled Shielding Gas:
- Using inert gases (like argon or helium) in a controlled environment can prevent the
introduction of moisture and other contaminants, further reducing the likelihood of porosity.
3. Material Preparation
- In an Additional Considerations:
- Equipment: Ensure that the welding equipment is functioning properly, with appropriate gas
flow rates and settings.
- Filler Materials: Use quality filler materials that are compatible with the base metals and
suitable for the welding process.
- Post-Weld Treatment: Inspect and possibly treat welds to ensure integrity, especially in critical
applications.
While an air-free environment can significantly reduce the risk of porosity, it is not a complete
solution on its own. Proper technique, equipment, and material handling are also crucial for
minimizing porosity in welded joints.

Chemical properties of Mg, Si, C, Zn

Here’s a brief overview of the chemical properties of magnesium (Mg), silicon (Si), carbon (C),
and zinc (Zn):
1. Magnesium (Mg)
- Atomic Number: 12
- Group: Alkaline earth metals
- Reactivity:
- Reacts readily with oxygen, forming magnesium oxide (MgO).
- Burns with a bright white flame when ignited.
- Compounds: Forms various compounds such as magnesium chloride (MgCl₂) and magnesium
sulfate (MgSO₄).
- Alloys: Often used in alloys to improve strength and reduce weight.
Applications
 Magnesium compounds are used as refractory material in furnace linings for producing
metals (iron and steel, nonferrous metals), glass, and cement.
 With a density of only two-thirds of the aluminum, it has countless applications in cases
where weight reduction is important, i.e. in airplane and missile construction.
 It also has many useful chemical and metallurgic properties, which make it appropriate

for many other non-structural applications.

 Magnesium components are widely used in industry and agriculture.

  Other uses include the removal of sulfur from iron and steel, photo-engraved plates in
the printing industry; reducing agent for the production of pure uranium and other
metals from their salts; flashlight photography, flares, and pyrotechnics.
2. Silicon (Si)
- Atomic Number: 14
- Group: Metalloids
- Reactivity:
- Reacts with halogens and some acids but is relatively inert at room temperature.
- Forms silicon dioxide (SiO₂) and various silicates.
- Compounds: Key component of glass, ceramics, and silicon-based polymers.
- Uses: Widely used in semiconductors and solar cells.
Applications
 Silicon is the principal component of glass, cement, ceramics, most semiconductor
devices, and silicones, the latter a plastic substance often confused with silicon.
 Silicon is also an important constituent of some steels and a major ingredient in bricks.
 It is a refractory material used in making enamels and pottery.
 Elemental raw silicon and its intermetallic compounds are used as alloy integrals to
provide more resistance to aluminum, magnesium, copper, and other metals.
 Metallurgic silicon with 98-99% purity is used as raw material in the manufacture of
organ silicic and silicon resins, seals, and oils.
 Silicon chips are used in integrated circuits. Photovoltaic cells for direct conversion of
solar energy use thin-cut slices of simple silicon crystals of electronic grade.
 Silicon dioxide is used as raw material to produce elemental silicon and silicon carbide.
 Big silicon crystals are used for piezoelectric glasses.
 Melted quartz sands are transformed in silicon glasses which are used in laboratories
and chemical plants, as well as in electric insulators.
 A colloidal dispersion of silicon in water is used as a coating agent and as an ingredient
for certain enamels.
It is known that silicon forms compounds with 64 out of the 96 stable elements and possibly
forms silicides with other 18 elements. Apart from metallic silicide’s, which are used in big
quantities in metallurgy, it forms important commonly used compounds with hydrogen, carbon,
halogens, nitrogen, oxygen and sulfur. Moreover, many useful organosilicic by-products.
3. Carbon (C)
- Atomic Number: 6
- Group: Nonmetals
- Reactivity:
- Can form a vast number of compounds (organic chemistry).
- Reacts with oxygen to form carbon dioxide (CO₂) or carbon monoxide (CO).
- Allotropes: Exists in various forms such as graphite, diamond, and amorphous carbon.
- Compounds: Forms compounds with many elements, including hydrocarbons and carbonates.
Application
 The free element has a lot of uses, including decoration purposes of diamonds in jewelry
or black fume pigment in automobile rims and printer’s ink.
 Another carbon form, graphite, is used for high-temperature crucibles, dry cells, and
light arch electrodes, for pencil tips, and as a lubricant.
 Vegetal carbon, an amorphous form of carbon, is used as a gas absorbent and bleaching
agent.
 Carbon compounds have plenty of uses. Carbon dioxide is used in drinks carbonatation,
in fire extinguishers, and, in the solid state, as a cooler (dry ice).
 Carbon monoxide is used as a reduction agent in many metallurgic processes.
 Carbon tetrachloride and carbon disulfide are important industrial solvents. Freon is
used in cooling systems.
 Calcium carbide is used to prepare acetylene; it’s used for welding and cutting metals, as
well as for the preparation of other organic compounds. Other metallic carbides have
important uses as heat-resistant and metal cutters.
4. Zinc (Zn)
- Atomic Number: 30
- Group: Transition metals
- Reactivity:
- Reacts with acids to produce hydrogen gas.
- Reacts slowly with oxygen in dry air but forms a protective oxide layer that prevents
further corrosion.
- Compounds: Forms zinc oxide (ZnO), zinc sulfide (ZnS), and zinc carbonate (ZnCO₃).
- Uses: Commonly used for galvanizing steel to prevent rusting and in various alloys.
Summary
- Mg: Lightweight, reactive with oxygen, forms various compounds.
- Si: Metalloid, forms silicates, and glass, key in electronics.
- C: Fundamental elements in organic chemistry, exist in multiple forms.
- Zn: Reactive with acids, protects against corrosion, and forms various compounds.

Each of these elements has unique properties that make them valuable in different industrial
and chemical applications.
The chemical properties of magnesium (Mg), silicon (Si), carbon (C), and zinc (Zn) that are
relevant in the context of flux used in welding and metalworking processes include:
1. Magnesium (Mg)
- Reactivity: Highly reactive with oxygen; burns brightly when ignited. This property helps
create a reducing atmosphere during welding, preventing oxidation.
- Alloying Agent: Often used to improve the properties of aluminum alloys, enhancing
strength and corrosion resistance.
- Oxidation: Forms magnesium oxide (MgO) when exposed to air, which can help protect
the weld area when used in flux formulations.
2. Silicon (Si)
- Deoxidizing Agent: Silicon acts as a deoxidizer in welding flux, helping to remove oxygen
from the weld pool and reducing porosity.
- Lowering Melting Point: Silicon can lower the melting point of the weld, facilitating
smoother flow and better fusion.
- Silicates: Forms silicate compounds in fluxes that enhance fluidity and help create a
protective slag over the weld.
3. Carbon (C)
- Strengthening Agent: In certain applications, carbon can enhance the hardness and
strength of the weld metal.
- Reactivity: Reacts with oxygen to form carbon dioxide (CO₂) during welding, which helps
shield the molten weld pool.
- Slag Formation: Contributes to the formation of slag, which protects the weld from
atmospheric contamination during solidification.
4. Zinc (Zn)
- Corrosion Resistance: Zinc is often used in flux formulations to improve the corrosion
resistance of the weld. It forms zinc oxide (ZnO), which can help protect the weld area.
- Low Melting Point: Zinc has a relatively low melting point, which aids in the melting process of
the flux.
- Deoxidizing Properties: Similar to silicon, zinc can help reduce oxides in the weld pool,
improving the quality of the weld.
Summary
- Mg: Provides a reducing atmosphere, improves alloy properties, and forms protective
oxides.
- Si: Acts as a deoxidizer, lowers the melting point, and improves fluidity.
- C: Enhances strength, contributes to slag formation, and helps shield the weld.
- Zn: Improves corrosion resistance, aids melting, and has deoxidizing effects.

These elements are essential in formulating effective welding fluxes that enhance the quality
and properties of welds.
Applications
 It is used principally for galvanizing iron, more than 50% of metallic zinc goes into
galvanizing steel, but is also important in the preparation of certain alloys.
 It is used for the negative plates in some electric batteries and for roofing and gutters in
building construction.
 Zinc is the primary metal used in making American pennies, and is used in die casting in
the automobile industry.
 Zinc oxide is used as a white pigment in watercolors or paints and as an activator in the
rubber industry.
  As a pigment zinc is used in plastics, cosmetics, photocopier paper, wallpaper, printing
inks, etc.,
 while in rubber production its role is to act as a catalyst during manufacture and as a
heat disperser in the final product.
 Zinc metal is included in most single tablets, it is believed to possess anti-oxidant
properties, which protect against premature aging of the skin and muscles of the body.

Frequently Asked Questions on Welding

1. What is welding?
- Welding is joining two materials like thermoplastics or metals at a high temperature by
melting the base material and filler metal.
2. What is meant by LASER?
- LASER is a device that emits high-intensity monochromatic light through optical
amplification based on the stimulated emission of electromagnetic radiation.
3. What is filler material?
- The filler material is the pool of molten material that aids in the formation of a strong
link between the base metal.
4. Which is the early method of welding?
- Forge Welding.
5. List the advanced methods of welding
 Laser beam welding
 electron beam welding
 magnetic pulse welding
 friction stir welding
What do E6013, and E7018 mean?
The designations E6013 and E7018 refer to specific types of welding electrodes, and each part
of the designation provides information about the electrode's characteristics:
E6013
- E: Indicates it is an electrode for arc welding.
- 60: Refers to the minimum tensile strength of the weld metal, which is 60,000 psi
(pounds per square inch).
- 1: Indicates the welding position. The "1" means it can be used in all positions (flat,
horizontal, vertical, and overhead).
- 3: Refers to the type of coating on the electrode. In this case, the "3" indicates a rutile
coating, which is designed for easy arc striking and stable arc performance.
Applications of E6013:
- Suitable for welding mild steel in various positions.
- Commonly used for general fabrication, light structural work, and thin-walled
applications.
E7018
- E: Indicates it is an electrode for arc welding.
- 70: Refers to the minimum tensile strength of the weld metal, which is 70,000 psi.
- 1: Indicates it can be used in all positions.
- 8: Refers to the type of coating. The "8" indicates a low hydrogen coating, which helps
reduce the risk of hydrogen-induced cracking.

Applications of E7018:
- Often used for critical applications, such as structural welding, where high strength and
low hydrogen content are necessary.
- Ideal for welding high-strength steels and in situations where a clean, sound weld is
required.
Summary
- E6013: General-purpose electrode for mild steel with good usability in various positions.
- E7018: Low-hydrogen electrode for high-strength applications, known for its toughness and
crack resistance.
Type of coating on the electrode
The coating on a welding electrode serves several important functions, and different types of
coatings can significantly influence the welding process and the quality of the weld. Here are
some common types of electrode coatings:
1. Rutile Coating
- Examples: E6013
- Characteristics:
- Provides a stable arc and easy arc initiation.
- Produces a smooth, flat bead with good appearance.
- Good for welding in all positions.
- Generates a slag that helps protect the weld from contamination.
2. Cellulosic Coating
- Examples: E6010
- Characteristics:
- Contains organic materials that produce a large amount of shielding gas.
- Ideal for welding in field conditions or outdoors.
- Provides good penetration and is used for root passes in pipe welding.
3. Basic (Low Hydrogen) Coating
- Examples: E7018
- Characteristics:
- Contains materials that help to absorb moisture and produce low hydrogen levels in the
weld.
- Reduces the risk of hydrogen-induced cracking.
- Suitable for welding high-strength steels and critical applications.
4. Iron Powder Coating
- Examples: E7014
- Characteristics:
- Contains iron powder to increase deposition rates.
- Produces a weld with good mechanical properties.
- Used for flat and horizontal welding positions.
5. High-Performance Coating
- Examples: E7015, E7016
- Characteristics:
- Designed for specific applications requiring enhanced mechanical properties.
- May contain various additives to improve arc stability and weld quality.
Summary
The choice of electrode coating affects the arc stability, penetration, ease of use, and
mechanical properties of the weld. Selecting the appropriate coating type is crucial for
achieving optimal results based on the specific welding application and materials being welded.
Welding Process Chart

Welding
Description Applications Advantages Considerations
Process

Uses a continuous
wire feed and Automotive, Fast, easy to Requires good
MIG (Metal
shielding gas fabrication, and automate, clean ventilation; needs
Inert Gas)
(typically argon or thin materials. welds. proper shielding gas.
CO₂).

Uses a non-
High-quality
consumable Slower process;
TIG (Tungsten Aerospace, art, and welds, excellent
tungsten electrode requires skilled
Inert Gas) thin metals. control,
and inert gas for operator.
versatile.
shielding.

Uses a consumable Simple

Stick (Shielded Construction, More cleanup
electrode coated in equipment,
Metal Arc repair, and outdoor required; can
flux to protect the good for thick
Welding) work. produce slag.
weld pool. materials.

Flux-Cored Arc Similar to MIG but Heavy equipment, Good for thicker Requires good
Welding uses a tubular wire construction, and materials; can be shielding; can
(FCAW) filled with flux. shipbuilding. used outdoors. produce slag.

Uses a continuously High deposition

Submerged Heavy industrial Requires flat
fed wire and a rates, minimal
Arc Welding applications, pipe surfaces; limited to
blanket of granular fumes and
(SAW) welding. specific positions.
flux. sparks.

Excellent
Plasma Arc Uses a plasma torch Aerospace and More complex
control, can
Welding to create a high- precision equipment; requires
weld very thin
(PAW) temperature arc. applications. skilled operation.
materials.

Laser Beam Uses a focused laser Automotive, High precision, High equipment
Welding (LBW) beam to melt the electronics, and minimal thermal costs; requires clear
Welding
Description Applications Advantages Considerations
Process

workpieces. precision work. distortion. line of sight.

Uses heat Limited to

Automotive and Fast and efficient
Resistance generated from overlapping joints;
appliance for thin
Welding resistance to requires precise
manufacturing. materials.
current flow. alignment.