Metal Bonding

Question 1

Riveting

Answer 1

a metal pin for passing through holes in two or more plates or pieces to hold them together, usually made with a head at one end, the other end being hammered into a head after insertion.

Question 2

Types of Riveting (3)

Answer 2

pop, hot, cold

Question 3

Pop Riveting

Answer 3

Pop riveting joins thin pieces of metal and plastics.
It is done by drilling a hole in the material then feeding the rivet through. Then the rivet pliers are pushed on to the pin of the rivet and the handles are pulled together. As this happens the pin head is pulled into the rivet and the end of the rivet is expanded. Eventually the pin will break off leaving the rivet permanently fixed in position holding the two pieces of plastic / aluminium together.

Question 4

cold riveting

Answer 4

While cold riveting is the process of heading-over rivets without first heating them. This is done with the help of rivets not over three eighths of an inch in diameter. 

Question 5

hot riveting

Answer 5

The hot riveting process uses heat and pressure to form fastener as the result the material being formed become malleable and collapses under pressure that is applied by the power-head.

Question 6

Nuts and bolts

Answer 6

Metal fasteners are of two kinds—those producing a permanent bond and those requiring either a releasable or a sliding bond. Screws, nuts and bolts, rivets, retaining rings and clamps are examples from the first category. Non-permanent fasteners include quick-release couplers and clamps intended for removal at a specified time and pins, which allow relative movement of fastened parts.
Metal fasteners must be strong to bear significant loads. In many cases they can be manufactured by casting techniques. Iron is a constituent of many types of metal fasteners, although titanium increasingly is coming into use in applications where strength must be balanced against light weight. In most applications where permanent bonding is required metal fasteners are replaceable by some form of welding or soldering.

Question 7

Cold Bonding (3)

Answer 7

Riveting
nuts and bolts
seams

Question 8

Seams

Answer 8

The lap seam is a basic metal seam where one piece overlaps the other. A “lap” is created by making a fold across the edge, then laying the lap over the other piece of metal, pounding flat and soldering, welding or securing with rivets. Lap seams are often used to connects two ends to make a cylinder and are used in making boilers, auto bodies, wall panels, metal sculpture and metal roofing.

Question 9

Heat Bonding

Answer 9

Welding, Brazing, Soldering

Question 10

Types of soldering

Answer 10

Hard, Soft, Silver

Question 11

Hard Soldering

Answer 11

In this type of soldering a solid solder unites two elements of metals by spreading out into the holes of the component that are unlocked due to high temperature. The space filler metal grips higher temperature more than 450oC/840oF. It comprises of two elements: Silver soldering and Brazing.

Question 12

Soft Soldering

Answer 12

Soft soldering is a process for fitting very small parts with low liquefying temperature, which have been broken during the procedure of soldering is performed at high temperature. In this process, a tin-lead alloy is used as space filler metal. The liquefying temperature of the space filler alloy must not be less than 400oC / 752oF. A gas torch is used as a heat source, for the procedure. Some of the examples of this kind of soldering metals include: tin-zinc for bonding aluminum, tin-lead for general usage; zinc-aluminum for aluminum, cadmium-silver for power at high temperature; lead-silver for strength higher than room temperature, weakening confrontation, tin-silver & tin-bismuth for electrical products.

Question 13

Silver Soldering

Answer 13

It is an unsoiled method supportive to fabricate small components, carrying out abnormal maintenance and built-up tools. It makes use of an alloy containing silver as a space filler metal. Though silver provides a free running individuality, yet silver soldering is not suggested for space filling, and thus, different flux is recommended for accurate silver soldering.

Question 14

Types of Welding

Answer 14

ARK, MIG, TIG

Question 15

MIG Welding

Answer 15

MIG welding uses a gun that is continuously fed with a consumable electrode. The process uses an external gas to shield the welded metal from environmental factors like oxygen making it continuous and quick. This method is easy to learn, produces less welding fumes, has a high electrode efficiency. MIG welding works well with a variety of alloys like stainless steel, aluminum, silicon bronze, magnesium, copper and nickel. It is used in automotive repairs, construction, plumbing, robotics, fabrication.

Question 16

TIG Welding

Answer 16

Is a difficult and time-consuming welding process. An autogenous weld can be created by melting two pieces of metal together without filler metal. TIG  produces high quality and spatter free welds of various alloys that can be very thin. However, it requires a highly skilled operator and external shielding gas and does not work on rusty or dirty materials. TIG welding is best used in aerospace welding, vehicle, motorcycle and bike manufacturing, tubing and in high precision welds.

Question 17

Brazing

Answer 17

The AWS defines brazing as a group of joining processes that produce coalescence of materials by heating them to the brazing temperature and by using a filler metal (solder) having a liquid above 840°F (450°C), and below the solidus of the base metals.
The very basics of brazing are defined by the joining of metals through the use of heat and a filler metal—one whose melting temperature is above 840°F (450°C) but below the melting point of the metals being joined.