 Hello friends, myself Dr. Narendra Kartikar, Assistant Professor, Department of Mechanical Engineering, Valachandra Institute of Technology, Solapur. Now we are going to see the discussion-compresentation on study of soldering. At the end of this lecture rather session, student will be able to understand the soldering process and also know where to apply it. The content for this presentation come discussion as follow introduction, introduction to joining process, introduction to soldering process, soldering process description, solders and solder fluxes, advantages, disadvantages and applications of soldering process itself. Let us go with the introduction of joining process itself. As we know there are basic manufacturing processes widely divided into the four major segments like casting where the melting of base metal rather raw material is going to be carried out and then converted into the required specification to get the expected output in the form of job. Still forming rather in this process the material is converted from raw material specification to the finished product in the plastic deformation itself. Joining processes where more than two elements are joined together as a permanent joint with the application of heat energy, filler material, flux material and or pressure, metal cutting where the metal raw material is converted into the finished product by the chip removal method. As we know no single or singular element that can be used effectively unless and otherwise it is assembled together to get the particularly expected output of that assembly. So to form an assembly the joining processes have the much more importance from that perspective. Welding as we know as just we had seen the welding is a permanent joint where the base metal as well as the filler material is converted from solid state to the liquid state where the base metal and filler material mixed together and after solidification it delivers one coalescence a bond formation a strong bond formation between the more than two elements. The soldering and brazing provides the permanent joint to the bond metal pieces itself. Soldering and brazing process lies somewhere in between fusion welding and solid state welding. In soldering and brazing the base metal is not converted from solid state to the liquid state itself. Let us see the introduction of soldering process. Soldering is a method of joining similar or dissimilar metals by heating them to a suitable temperature and by means of filler metal called solder. Having liquidous temperature not exceeding 450 degrees Celsius and below the solidus of the base metal. Through soldering obtain a good joint between the two plates the strength of the joint is limited by the strength of filler metal used over there. No melting of base metal but filler metal wets and combines with the base metal to form metallurgical bond itself. Soldering similar to brazing and many of the same heating methods are used. Solder metal called solder. Most commonly associated with electrical and electronic assembly that is wire soldering. At this stage of the session are you able to recall or share some of the parts where different geometries are joined with a soldering process. Enlist such soldering parts which you had seen earlier anywhere in real time. Just enlist such parts. I hope everyone has written their particular experience regarding the joints formed with the means of soldering process. Let us go with the soldering process itself. Basic operations in soldering for making soldered joint following operations are required to be performed in a sequential manner. This particular image typically reflects the soldering process in real time where you can see the heat addition is going to be carrying out through the means of particularly heat source as well as the filler material is going to be filled in between the gap of two base metal itself. Soldering process sequentially will see stepwise one by one. Hitting and fitting of metal parts together. Filler metal on heating flows between the closely placed adjacent surfaces due to capillary action. Thus, closer the parts the more is the solder penetration. This means that the two parts should be shaped to fit closely so that the space between them is extremely small to be filled completely with a solder by the capillary action. If a large gap is present capillary action will not take place and the joint will not be strong enough. Second stage of soldering process cleaning of surfaces. This is due to second stage of soldering process cleaning of surfaces. This is done to remove dirt, grease or any other foreign material from the surface piece to be soldered in order to get a sound joint. If surfaces are not clean strong atomic bond will not form. Third stage of soldering process flux application. Soldering cannot be done without a flux. Even if a metal is clean it rapidly acquires an oxide film of submicroscopic thickness due to heat and this film insulates the metal from the solder preventing the surface to get weighted by solder. This film is broken and removed by the flux. The flux is applied when the parts are ready for joining. Application of heat and solder. The next step of soldering process. The parts must be held in a vise or with a special work holding devices so that they do not move while soldering. The parts being soldered must be heated to solder melting and solder alloying temperature before applying the solder for soldering to take place the assembly. So that the heat is most effectively transmitted to being soldered. As soon as the heat is applied the flux quickly breaks down the oxide film the insulating oxide layer barrier between the surface and solder. Now solder is applied which is immediately melt and metal to metal contact is established through the medium of molten solder. Finally the surplus solder is removed and the joint is allowed to cool. So torches dipped the part in a molten solder or other method are also used for soldering. Soldering process tools here the image shows the varieties of tools that can be help out for the successful conduction of soldering process. As per the particular labels you can see over here vise safety glasses, solder suckers, solder tool, diagonal cutters, nose pliers, solder, solder wick, damp sponge, soldering iron. Solders, solders are alloy of lead and tin. Solder may also contain other elements like cadmium and antimony in small quantities. The percentage composition of tin and lead determines the physical and mechanical properties of solder and the joint made. Most solder is available in many forms bars, sticks, fields, wires, strips and so on. It can be obtained in a circular or semicircular ring or any other desired shape. Sometimes the flux is included with the solder. For example a cold wire is a tube of solder filled with a flux, solder fluxes. The flux does not constitute a part of the soldered joint, zinc chloride, ammonium chloride, hydrochloric acid are the example of flux commonly used in soldering. The function of fluxes in a soldering is to remove the oxides and other surface compounds from the surfaces to be soldered by displacing or dissolving them. Soldering fluxes may be classified into four groups. Organic fluxes, Rosin fluxes, Spatial fluxes for specific applications. Some of the advantages of soldering process. Low power is required, low process temperature, microscopic, microstructure is not affected by heat, easily automated process, dissimilar materials may be joined together which is not possible easily with other joining rather welding processes. High variety of materials may be joined, thin wall parts may be joined easily. Some of the disadvantage of soldering process, large sections cannot be joined, fluxes may contain toxic components, it delivers the low strength of joint as compared to welding. Careful removal of flux residual is required in order to prevent the erosion. Careful removal of the flux residual is required in order to prevent the corrosion. Applications of soldering process, soldering is used in electronics and in jewelry metalwork. Some refrigeration components are often assembled and repaired by high temperature silver soldering process can be used for semi-permanent patch for a leak in a container or cooking vessel. Electronic soldering connects electrical wiring and electronic component to printed circuit board that is PCB. Some of the references are introduction to basic manufacturing process, workshop technology Rajendra Singh, textbook of workshop technology manufacturing process Khurmi Gupta, NPTEL study material and so on. Thank you.