Category: Casting And Welding

A number of defects can occur during the welding processes, some of them are shown in Figure 20.51. There are many other defects which are discussed in the following paragraphs. Figure 20.51 Welding Defects Cracks: Cracks occur in the welded joint due to improper welding and solidification of different metals. Cracks may be of the following types. There…

In braze welding, the molten filler metal is not distributed at joint by capillary action as it happens in brazing or soldering but it is deposited at the point where the weld is required to be made as in the case of gas welding.

Brazing is a hard soldering process, but in this process, metal pieces are heated which are to be joined in this place of the bit as in soldering. In a brazing, spelter is used. It is a mixture of copper, zinc, and tin. It is stronger in comparison to soldering joint.

Soldering is a process of joining two metals by applying low melting point metal or alloy in the gap between the joining parts. The metal or alloy used for filling or joining is known as solder. The melting point of solder is less than 450°C. Solders are divided into two categories. Flux Used: Chlorides fluxes (zinc…

Thermit welding is similar to casting. A mixture of powered aluminium and iron oxide is placed inside a vessel. The mixture is ignited by heating to about 1,550°C with the help of barium oxide powder. A chemical reaction takes place in a vessel as shown in Figure 20.50. Figure 20.50 Thermit Welding Due to the chemical action,…

In the welding technique, a stream of high-speed electrons strikes on work surface where the kinetic energy of electrons transferred to the work material produces intense heat. The metal can melt or vaporize depending on the intensity of heat generated. The same process is also used for machining purposes. The electron beam is produced in…

In the welding technique, a stream of high-speed electrons strikes on work surface where the kinetic energy of electrons transferred to the work material produces intense heat. The metal can melt or vaporize depending on the intensity of heat generated. The same process is also used for machining purposes. The electron beam is produced in…

Laser is a highly coherent beam of electromagnetic radiation with wavelength varying from 0.1 to 70 mm. It may be used for machining or welding purposes depending on the wavelength of radiation used. Figure 20.47 shows schematic diagram of laser beam welding. A coiled xenon flash tube is placed around the ruby rod and the internal…