Engineering Materials

Question 1

single element that is not combined with any other
chemical element. It is too soft, low in strength, or low in some
other desired property to be used in any commercial

Answer 1

Pure metal

Question 2

mixture of two or more metals producing a new metal

Answer 2

Alloy

Question 3

It is a pure ferrite.

Answer 3

Iron

Question 4

produced from ore of hematite or magnetite in the blast furnace by melting with limestone and coke

Answer 4

Pig iron

Question 5

with carbon content of 1.7 to 6/7%. It is low cost, good casting property, high compressive strength, high wearing resistance, brittle and lower tensile strength

Answer 5

Cast iron

Question 6

• It is a molten iron with carbon added into it that is cast into
  an ingot and then rolled, forged, hammered, pressed, or
  machine into desired shape
• Structural steel, steel bars and cylinders, and steel plates
  are commonly used as machine elements and frames

Answer 6

Steel

Question 7

durable to shock because the mild steel in the center layer is deformable and has higher wear
resistance than hard steel at the outer side. It is usually used for moldboard and share of a plow

Answer 7

Soft-centered steel

Question 8

with carbon content not exceeding 0.25%

Answer 8

Low-carbon steel

Question 9

contains 0.25 to 0.50% carbon. It is usually used in making structural and machinery steel.

Answer 9

Medium-carbon steel

Question 10

carbon content is above 0.50%. It is usually used in the manufacture of spring and tool steel.

Answer 10

High-carbon steel

Question 11

contains carbon of 0.15 to 0.25%. It is malleable and easy to cut and weld. Most parts of agricultural machines are made of this kind of metal.

Answer 11

Mild steel

Question 12

a medium-carbon steel used for
components of machines requiring greater strength and hardness, such as axles for power tillers, hitch pin, spike tooth of threshers and shellers, connecting rods, etc

Answer 12

Cold-rolled steel

Question 13

steel that has been roll-pressed at a very high temperature over 1,700°F which is above the re-crystallization temperature of steel. It is softer as compared to cold-rolled steel. It can be easily folded and rolled to form air ducts, chutes, etc

Answer 13

Hot-rolled steel

Question 14

1% Ni, 11-14% Cr, 0.6% Mn, 0.6% Si. It has high resistance to corrosion and oxidation. It is used for fabrication of dairy, food, equipment. Standard materials such as valves, nozzles, and etc. are examples of the use of stainless steel

Answer 14

Stainless-steel

Question 15

a steel manufactured under carefully controlled condition with carbon content between 1,7% to 1.5% commonly used as machine tool and other machine parts that require strength such as teeth for slow-moving shredders, special gears, pulley, etc

Answer 15

Tool steel

Question 16

– steel that is processed by cold drawing, cold rolling, or heat treatment to give elastic property to the metal

Answer 16

Spring steel

Question 17

a piece of metal which has been rolled into a sheet of 3/16in. or less in thickness. Commonly available sizes are 3’-wide x 6’-long and 4’-wide x 8’-long. The thickness is expressed
in terms of gauge number, which is equivalent to number of
sheets in 1in.-thick pile of metal sheet

Answer 17

Sheet

Question 18

long sheets of metal that is less than 12in. Wide

Answer 18

Strips

Question 19

metal with thickness over 3/16in. Commonly available

size is 4’-wide x 8’-long. Thickness is given in terms of mm or in inch

Answer 19

Plate

Question 20

made of different shapes and are usually available in standard length of 20ft or 6m. They are purchased in terms of quantity, shape, size, and kind of metal used.

Answer 20

Metal bars

Question 21

commonly used in the construction of agricultural machines. They are specified in terms of quantity wanted, the kind of material and shape, size, and length of each piece.

Answer 21

Structural shapes

Question 22

include all hollow metal shapes such as pipes and tubes. They are available in round, square, and
rectangular shapes. Specifications are given in terms of shape,
schedule number, size, and length

Answer 22

Tubular products

Question 23

Includes all metals such as copper, aluminum, magnesium, and zinc in which iron is not present in large amount.

Answer 23

Non-ferrous

Question 24

- Large group of materials 
consisting of combination of 
carbon and oxygen, hydrogen, 
nitrogen, and other and organic 
elements
- Non-metallic materials that can be molded into shape. They are light in weight, resistant to deterioration by moisture, low elasticity and thermal conductivity, and good 
color range.

Answer 24

Plastic

Question 25

- Materials ranging from glass to furnace brick. - These include ceramic oxides, glass-ceramics, carbides and nitrides.

Answer 25

Engineering ceramics

Question 26

- The oldest engineering material that includes jute, flax, and hemp - Usually used for engineered products such as rope, cordage, nets, water hose, and containers. Plant and animal fibers are used for felt, paper, brushes, and heavy structural cloths

Answer 26

Fiber

Question 27

- A non-crystalline or amorphous solid. - Types include soda-lime glass, Borosilicate glass, lead-alkali glass, aluminosilicate glass, silica glass, and fused silica.

Answer 27

Glass

Question 28

- Standard parts of agricultural machines play a very important role in the construction and performance of the machine - They are especially manufactured and mass produced to perform a specific function. - They can be readily purchased from stores and hardware, and are available in various sizes.

Answer 28

Standard materials

Question 29

It is used to hold power transmission parts in position

Answer 29

Bearings

Question 30

They are used to prevent oil or any fluid from leaking through bearing parts

Answer 30

Oil seals

Question 31

- Used to transmit power from the driver shaft to the driven shaft

Answer 31

Pulley and belt

Question 32

Part of the machine that transmits power at higher torque but at lower speed from the driver to the driven shaft.

Answer 32

Sprocket and chain

Question 33

They are used in transmitting power when the machines are | compact and shafts are placed close together.

Answer 33

Gears

Question 34

- They are a direct-drive transmission system used to transmit power to a misaligned shaft. - Commonly used in driving attached implement like rotary tiller, post-hole digger, and fertilizer applicator to the power take-off shaft of a tractor

Answer 34

Universal joints and flexible shafts

Question 35

- is a device that produces intermittent motion or a specific motion to a member called follower - It is a disc with a lobe on one side and, when rotated, produces intermittent motion

Answer 35

Cam

Question 36

They are used to hold machine parts together

Answer 36

Bolts and nuts

Question 37

They are externally threaded fasteners capable of being inserted into holes in assembled parts of mating with a preformed internal thread or forming its own thread.

Answer 37

Screws

Question 38

They are low-cost permanent fasteners well suited to automatic assembly operation.

Answer 38

Rivets

Question 39

- They are used on the end either beneath the head of the bolt or beneath the nut. - They are used primarily as a seat to distribute load in a fastener system.

Answer 39

Washers

Question 40

They are inexpensive and effective fastener and are used when loading in shear. They are commonly used to fasten shaft in some control linkages

Answer 40

Pins

Question 41

They are used to provide a removable shoulder to accurately locate, retain, or lock components on shaft or in bores and housing

Answer 41

Retaining rings