9.11 Consumable electrode for manual metal arc welding of steel is made of
(a) Tungsten
(b) Steel
(c) Copper
(d) Cadmium copper
9.12 Electrode for gas metal arc welding of steel is
made of
(a) Tungsten
(b) Steel
(c) Copper
dCadmium copper
The Correct Answer and Explanation is :
9.11 Consumable electrode for manual metal arc welding of steel is made of:
Correct answer: (b) Steel
Explanation:
In manual metal arc welding (MMAW), also known as stick welding, the electrode used is consumable, meaning it melts and becomes part of the weld pool as the process continues. These electrodes are made of steel because steel electrodes are capable of transferring the necessary heat to the workpiece while providing a weld metal that is strong and adheres well to the steel being welded.
The electrode consists of a steel core wire, which is coated with a flux. The steel core provides the metal that will form the weld, and the flux coating protects the weld pool from atmospheric contamination, stabilizes the arc, and helps to remove impurities from the weld. The flux can also provide additional alloying elements depending on the type of steel being welded.
Tungsten (a) is used for non-consumable electrodes, such as in TIG (tungsten inert gas) welding. Copper (c) is commonly used in other components of welding equipment, like cables, but not in consumable electrodes. Cadmium copper (d) is used in specific applications but is not the standard for manual metal arc welding of steel.
9.12 Electrode for gas metal arc welding of steel is made of:
Correct answer: (b) Steel
Explanation:
In gas metal arc welding (GMAW), commonly referred to as MIG welding, the electrode is a consumable wire that melts and joins the workpieces. These electrodes are typically made of steel, as it is a versatile material that can be used for welding a variety of steel alloys. The steel wire is fed continuously into the weld pool through a welding gun, where it combines with the molten base material to create the weld joint.
The electrode for GMAW is often available in various compositions depending on the type of steel being welded. Steel electrodes are chosen to match the mechanical properties of the steel being welded, providing strong, durable welds. While other materials like aluminum, copper, or specific alloys may be used in certain welding processes, steel is the most common electrode material for GMAW when welding steel.
Tungsten (a) is used for TIG welding, not GMAW. Copper (c) is often used for the electrode material in TIG welding, where it is non-consumable, and cadmium copper (d) is used in some specialized applications, but not in the standard electrodes for GMAW of steel.