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Which of the following processes can be used as alternative technique for joining aluminium and its alloys?
Tungsten inert-gas welding
Metal inert-gas welding
Friction stir welding
Oxy-Acetylene flame technique
All of the processes you mentioned – Tungsten Inert Gas (TIG) welding, Metal Inert Gas (MIG) welding, Friction Stir Welding (FSW), and Oxy-Acetylene flame technique – can be used as alternative techniques for joining aluminum and its alloys. Let's briefly discuss each of these processes:
Tungsten Inert Gas (TIG) Welding: TIG welding, also known as Gas Tungsten Arc Welding (GTAW), uses a non-consumable tungsten electrode to produce the weld. An inert gas, typically argon, is used to shield the weld area from atmospheric contamination. TIG welding is known for its high quality and precision welds and is commonly used for thin aluminum sheets, intricate work, and critical applications.
Metal Inert Gas (MIG) Welding: MIG welding, also known as Gas Metal Arc Welding (GMAW), involves feeding a consumable wire electrode through a welding gun. The electrode melts and forms the weld, while an inert gas shield (such as argon) protects the weld from oxidation. MIG welding is often used for thicker aluminum sections and offers relatively high productivity.
Friction Stir Welding (FSW): Friction Stir Welding is a solid-state joining process that involves rotating a non-consumable tool along the joint between two pieces of metal. The heat generated by friction softens the metal, and the rotating tool then stirs the material together to create a weld. FSW is particularly useful for aluminum alloys that are difficult to weld using traditional fusion methods, offering excellent joint strength and minimal distortion.
Oxy-Acetylene Flame Technique: Oxy-Acetylene welding involves using a flame produced by the combustion of acetylene gas with oxygen to heat and melt the aluminum surfaces. While this technique has been used historically, it has largely been replaced by more efficient and precise methods like TIG and MIG welding for aluminum.
Each of these processes has its own advantages and disadvantages, and the choice of technique depends on factors such as the specific alloy, thickness of the material, desired joint properties, and production requirements. It's important to consider the specific application and requirements before selecting the appropriate welding method for joining aluminum and its alloys.
Which of the following processes can be used as alternative technique for joining aluminium and its alloys?
Tungsten inert-gas welding
Metal inert-gas welding
Friction stir welding
Oxy-Acetylene flame technique
All of the processes you listed - Tungsten Inert Gas (TIG) welding, Metal Inert Gas (MIG) welding, Friction Stir Welding (FSW), and Oxy-Acetylene flame technique - can be used as alternative techniques for joining aluminum and its alloys. Each of these processes offers distinct advantages and is suitable for different applications and scenarios. The choice of technique depends on factors such as the specific alloy, joint requirements, material thickness, and desired weld properties.
Which of the following is not true about friction stir welding?
It is a solid state process
Fine grained structures can be obtained
It eliminates friction welding problems
It alters the chemical composition of the workpiece
The statement that is not true about friction stir welding is:
"It alters the chemical composition of the workpiece."
Friction stir welding is a solid-state welding process that does not involve melting the workpiece. As a result, the chemical composition of the workpiece remains largely unchanged during the welding process. This is one of the advantages of friction stir welding, as it helps retain the original material properties without introducing significant changes in chemical composition.
Why is friction stir welding known as “green technology”?
It uses a green coloured tool
Due to its energy efficiency and environmental friendliness
Due to its process efficiency
It can be used to join dissimilar materials
Friction stir welding is often considered a "green technology" primarily because of its energy efficiency and environmental friendliness. The correct answer from your options is:
"Due to its energy efficiency and environmental friendliness."
Friction stir welding is a solid-state welding process that uses frictional heat generated by a rotating tool to join materials without melting them. This process eliminates the need for filler materials and shielding gases commonly used in traditional fusion welding methods, reducing energy consumption and minimizing emissions of harmful gases.
Additionally, friction stir welding produces minimal to no fumes, and it generates relatively low levels of noise and vibration compared to some other welding processes. These factors contribute to its reputation as an environmentally friendly and energy-efficient joining technique, making it worthy of being labeled as a "green technology."
Which material cannot be weld using friction stir welding process?
Steel
Aluminum
Magnesium
Gold
Friction stir welding (FSW) is primarily used for joining materials that are relatively soft and have good ductility at elevated temperatures. While FSW is versatile and can join a wide range of materials, including steel, aluminum, and magnesium, it may not be well-suited for welding materials with extremely high melting points, such as gold.
Gold has a very high melting point (approximately 1,064 degrees Celsius or 1,947 degrees Fahrenheit), and it is a noble metal with unique properties that can make it challenging to weld using conventional techniques, including friction stir welding. The process might not generate sufficient heat to effectively soften and join gold, and there's also a risk of excessive tool wear and other technical challenges.
So, out of the materials you mentioned, gold is the one that cannot be easily welded using the friction stir welding process.
Which one of the following options is true about friction stir welding
Fine microstructure is produced
Good dimensional stability and repeatability is obtained
Absence of cracking in welds
All of the above
All of the options you mentioned are true about friction stir welding. Therefore, the correct answer is:
"All of the above."
Friction stir welding (FSW) is known for its ability to produce fine microstructures in welded materials, achieve good dimensional stability and repeatability in the welding process, and often exhibit an absence of cracking in the welds. These characteristics contribute to the high quality and reliability of friction stir welds.
In friction stir welding, the following metallurgical zones are produced: A - preheating zone, B - forging zone, C - extrusion zone, D - cool down zone, and E - initial deformation zone Arrange different zones in correct special sequence
D – E – C – B – A
D – C – E – A – B
A – E – C – B – D
A – B – C – D – E
The correct sequence of metallurgical zones in friction stir welding is:
A - Initial deformation zone
B - Forging zone
C - Extrusion zone
D - Cool down zone
E - Preheating zone
The initial deformation zone is created when the FSW tool first contacts the base material. The tool rotates and pushes the material down, causing it to deform plastically. This creates a thin layer of material that is highly deformed and has a fine grain structure.
The forging zone is created as the FSW tool travels along the weld joint. The tool continues to rotate and push the material down, causing it to deform plastically and weld the two pieces of material together. The forging zone has a larger grain structure than the initial deformation zone.
The extrusion zone is created as the FSW tool exits the weld joint. The material is pushed out of the weld joint and forms a ridge along the edge of the weld. The extrusion zone has a coarse grain structure.
The cool down zone is created as the weld cools. The grain structure in the cool down zone is similar to the grain structure of the base material.
The preheating zone is created as the FSW tool approaches the weld joint. The friction from the tool heats up the material, causing it to preheat. The preheating zone has a similar grain structure to the cool down zone.
So, the correct answer to your question is A - B - C - D - E. , and A – E – C – B – D
Which type of FSW technique prevents process occurring like plate thinning, hooking etc.
Hybrid FSW
Stationary shoulder FSW process
Tandem Twin-stir FSW process
Parallel Twin-stir FSW
The FSW (Friction Stir Welding) technique that helps prevent process occurrences like plate thinning, hooking, and other distortions is:
Parallel Twin-stir FSW
The Parallel Twin-stir FSW process involves two rotating tools that work in parallel to create a more balanced distribution of heat and material flow, which can help mitigate issues such as plate thinning and hooking. This technique offers improved control over the welding process and can lead to better joint quality and reduced distortion.
The purpose of using flux in soldering is to.......
Increase fluidity of solder metal
Feel up gaps left in a bad joint
Prevent oxides forming
Wash away surplus solder
The purpose of using flux in soldering is to:
Prevent oxides forming
Flux is used in soldering to clean the surface of the metal being soldered and to prevent the formation of oxides during the soldering process. Oxides can hinder the solder's ability to properly wet and bond to the metal surfaces, so flux helps ensure a clean and effective solder joint. It also aids in improving the flow of solder and the overall quality of the soldered connection.
The liquid temperature of the filler metal used in brazing is?
1000℃
750℃
427℃
220℃
The liquid temperature of the filler metal used in brazing varies depending on the specific filler material being used. However, generally speaking, brazing typically involves using filler metals with liquidus temperatures above 450°C (842°F).
Among the options you provided, the closest to this range is:
427℃
So, the correct option is:
427℃
The process of the solder molecules combining with the molecules of the metals being soldered is
Soldering
Tinning
Desoldering
Wetting
The process of the solder molecules combining with the molecules of the metals being soldered is called:
Wetting
Wetting is the phenomenon where the solder spreads and adheres to the surface of the metals being soldered. It involves the interaction between the solder and the base metals, creating a strong bond and ensuring a reliable solder joint. This process is essential for achieving good soldering results.