Sub Module 7.15: SOLDERING

Soldering:


Soldering is a process of joining two metals without melting them.

Soldering differs from welding in that it is done at considerably lower temperatures so that the parent metals do not melt and fuse together.

Instead, a fusible and, usually, non-ferrous alloy (with a lower melting point) is applied between the heated metals of the joint, such that the fusible alloy forms a metallic bond with the parent metals and, on cooling, creates a solid joint.

Tinning:

Before an iron can be used for soldering, the contact surfaces must be given a coating of tin or solder this process is called “tinning” the iron.

Solders:

Ordinary soft solder is a fusible alloy consisting chiefly of tin and lead. It is used to join two or more metals at temperatures below their melting point.


The standard grades of soft solder are as follows.

1. Tinman's

2. Electrician's

3. Lead Silver

The two basic methods of soldering are:

1. Hard Soldering: done at temperatures in excess of 500°C .

2. Soft Soldering: done at temperatures within the range of 180°C to 330°C, which, consequently, create joints of lower strength (but less expense) than those achieved by the hard-soldering methods.

Fluxes for soft soldering are often classified into two groups, which are the:

Active group: which are corrosive or acid fluxes

Passive group: which are non-corrosive fluxes.

Now lets check your knowledge through this quiz.  

https://docs.google.com/forms/d/1JbGtVJ8fcPljkRp2MOk-QmfcNs7cdvvrO0GP4Lsqbzk/edit?usp=drivesdk&chromeless=1

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