1
Q
Define metal casting.
A
The process of pouring molten metal into a mold to create a desired shape.
2
Q
What is the purpose of gating systems in casting?
A
To control the flow of molten metal into the mold cavity.
3
Q
True or false: Pouring temperature affects the quality of the casting.
A
TRUE
Higher temperatures can improve fluidity but may lead to defects.
4
Q
Fill in the blank: Mold materials include _______ and sand.
A
Ceramics
5
Q
What is a runner in casting?
A
A channel that directs molten metal from the pouring cup to the mold.
6
Q
Define draft angle.
A
The angle that allows easy removal of the casting from the mold.
7
Q
What is the role of risers in casting?
A
To provide additional molten metal to compensate for shrinkage during solidification.
8
Q
True or false: Cold shuts are defects caused by premature solidification.
A
TRUE
They occur when two streams of metal fail to fuse.
9
Q
Fill in the blank: Vent systems are used to allow _______ to escape from the mold.
A
Gases
10
Q
What is investment casting?
A
A precision casting process using a wax pattern coated in ceramic.
11
Q
Define sand casting.
A
A casting process using sand molds to shape molten metal.
12
Q
What does pouring rate affect in casting?
A
The quality and integrity of the final casting.
13
Q
True or false: Chills are used to speed up solidification in casting.
A
TRUE
Chills absorb heat and promote faster cooling.
14
Q
Fill in the blank: Core is used to create _______ within a casting.
A
Hollows
15
Q
What is lost foam casting?
A
A process where a foam pattern is vaporized to form a mold.
16
Q
Define casting defects.
A
Imperfections in castings that can affect performance and aesthetics.
17
Q
What is the purpose of mold release agents?
A
To prevent the casting from sticking to the mold.
18
Q
True or false: Metal fatigue is a concern in casting design.
A
TRUE
It affects the durability and lifespan of the casting.
19
Q
Fill in the blank: Thermal expansion must be considered in _______ design.
A
Mold
20
Q
What is a pouring basin?
A
A reservoir that holds molten metal before it enters the mold.
21
Q
Define metal casting.
A
The process of pouring molten metal into a mold to create a desired shape.
22
Q
What is the purpose of a riser?
A
To provide additional molten metal to compensate for shrinkage during solidification.
23
Q
True or false: Chills are used to speed up cooling in metal casting.
A
TRUE
Chills are often made of metal and placed against the mold.
24
Q
Fill in the blank: Shrinkage occurs when metal _______ as it cools.
A
solidifies
25
What is a **chill**?
A device used to absorb heat from molten metal and promote faster cooling.
26
Define **shrinkage cavity**.
A void that forms in a casting due to insufficient molten metal during solidification.
27
What are the **stages of shrinkage** in metal casting?
Liquid shrinkage, solidification shrinkage, and cooling shrinkage.
28
True or false: **Risers** should be located at the top of a mold.
FALSE
## Footnote
Risers are typically placed at the highest point to allow gas escape.
29
What is the role of **solidification** in casting?
To transform molten metal into a solid state, forming the final shape.
30
Fill in the blank: **Risers** help prevent _______ in castings.
shrinkage defects
31
Define **liquid shrinkage**.
The reduction in volume of molten metal as it cools before solidification.
32
What is **solidification shrinkage**?
The decrease in volume that occurs when metal transitions from liquid to solid.
33
True or false: **Chills** can be used to control the cooling rate.
TRUE
## Footnote
This helps in achieving desired mechanical properties.
34
What is the **benefit of using risers**?
They ensure that the casting remains filled with molten metal during cooling.
35
Fill in the blank: **Cooling shrinkage** occurs as metal _______ after solidification.
continues to cool
36
Define **shrinkage allowance**.
The intentional increase in mold size to compensate for metal shrinkage.
37
What is the effect of **chills** on casting quality?
They can improve the microstructure and reduce defects in the final casting.
38
True or false: **Risers** can be reused in multiple castings.
FALSE
## Footnote
Risers are typically consumed during the casting process.
39
What is the **function of a mold** in casting?
To shape the molten metal as it solidifies into the desired form.
40
Fill in the blank: **Risers** are also known as _______ reservoirs.
metal
41
Define **metal casting**.
The process of pouring molten metal into a mold to create a desired shape.
42
What is the purpose of a **core** in metal casting?
To create internal cavities or complex shapes within a cast part.
43
True or false: **Chaplets** are used to support cores during casting.
TRUE
## Footnote
Chaplets ensure cores remain in position while the mold is filled with molten metal.
44
Fill in the blank: A **core** is typically made of _______.
Sand or metal
45
What is a **chaplet**?
A small support used to hold a core in place within a mold.
46
Define **sand core**.
A core made from sand, used to form internal shapes in castings.
47
True or false: Cores can be made from ceramic materials.
TRUE
## Footnote
Ceramic cores are used for high-temperature applications.
48
What is the main function of **chaplets**?
To prevent cores from floating during the pouring of molten metal.
49
Fill in the blank: **Cores** are often used in _______ casting.
Sand
50
What is a **shell core**?
A core made from a thin shell of sand or resin, used for precision.
51
Define **core print**.
A feature on a mold that helps locate and support a core.
52
True or false: Cores can improve the mechanical properties of castings.
TRUE
## Footnote
Cores can enhance strength and reduce weight in certain designs.
53
What is the role of **core sand**?
To form cores that can withstand the heat of molten metal.
54
Fill in the blank: **Chaplets** are typically made of _______.
Metal
55
What is the advantage of using a **core**?
It allows for complex internal geometries that are difficult to achieve otherwise.
56
Define **core removal**.
The process of extracting the core from the casting after it has cooled.
57
True or false: Cores are always removed after the casting process.
FALSE
## Footnote
Some cores may remain in the final product for structural purposes.
58
What is a **metal core**?
A core made from metal, used for high-strength applications.
59
Fill in the blank: **Cores** can be used to create _______ in castings.
Hollow sections
60
What is the impact of **core design** on casting quality?
Proper core design can significantly affect dimensional accuracy and surface finish.
61
Define **investment casting**.
A precision casting process where a wax pattern is coated with a ceramic shell.
62
True or false: **Investment casting** is suitable for complex shapes.
TRUE
## Footnote
It allows for intricate designs and fine details.
63
What is the main material used in **investment casting** molds?
Ceramic materials are primarily used for molds in investment casting.
64
Fill in the blank: **Investment casting** is also known as _______.
Lost-wax casting
65
What is the first step in the **investment casting** process?
Creating a wax pattern that represents the final product.
66
Define **lost foam casting**.
A casting process where a foam pattern is used, which is vaporized during casting.
67
True or false: **Lost foam casting** uses a reusable pattern.
FALSE
## Footnote
The foam pattern is destroyed during the casting process.
68
What is a key advantage of **lost foam casting**?
It allows for complex shapes and reduces the need for machining.
69
Fill in the blank: In **lost foam casting**, the foam pattern is _______ during pouring.
Vaporized
70
What type of materials can be cast using **investment casting**?
Metals such as aluminum, steel, and titanium can be cast.
71
Define **shell mold** in investment casting.
A thin shell of ceramic material used to form the mold.
72
True or false: **Investment casting** can produce parts with tight tolerances.
TRUE
## Footnote
It can achieve tolerances of ±0.5%.
73
What is a disadvantage of **investment casting**?
It can be more expensive than other casting methods due to the process complexity.
74
Fill in the blank: **Lost foam casting** is often used for _______ parts.
Large industrial
75
What is the role of the **ceramic shell** in investment casting?
It provides strength and shape retention during metal pouring.
76
True or false: **Lost foam casting** requires a sand mold.
FALSE
## Footnote
It uses a mold created from the foam pattern.
77
What is the typical temperature range for **investment casting**?
Typically between 1,200°C to 1,600°C depending on the metal.
78
Define **pattern removal** in investment casting.
The process of melting or burning out the wax pattern after shell formation.
79
Fill in the blank: **Lost foam casting** is a form of _______ casting.
Expendable
80
What is the purpose of **coating** in investment casting?
To create a strong mold that can withstand high temperatures.
81
Define **die casting**.
A metal casting process that forces molten metal into a mold under high pressure.
82
True or false: **Die casting** is suitable for high-volume production.
TRUE
## Footnote
Die casting is efficient for producing large quantities of parts with consistent quality.
83
What is the main material used in **die casting**?
Aluminum, zinc, and magnesium alloys are commonly used.
84
Fill in the blank: **Permanent mold casting** uses _______ molds.
Metal
85
Define **permanent mold casting**.
A casting process using reusable molds to produce metal parts.
86
True or false: **Permanent mold casting** can produce complex shapes.
FALSE
## Footnote
This method is better for simpler shapes compared to sand casting.
87
What is the primary advantage of **die casting**?
High precision and smooth surface finish of cast parts.
88
Fill in the blank: **Die casting** typically requires _______ temperatures.
High
89
What is a disadvantage of **die casting**?
High initial tooling costs can be a barrier for small production runs.
90
True or false: **Permanent mold casting** is limited to non-ferrous metals.
TRUE
## Footnote
Commonly used for aluminum and copper alloys.
91
What is a key feature of **die casting** molds?
They are made from hardened steel or iron to withstand high pressure.
92
Fill in the blank: **Permanent mold casting** is often used for _______ parts.
Automotive
93
What is the cooling method in **permanent mold casting**?
Cooling occurs through the mold walls, allowing for faster solidification.
94
Define **hot chamber die casting**.
A die casting method where the molten metal is kept in a chamber at high temperature.
95
True or false: **Cold chamber die casting** is used for high melting point metals.
TRUE
## Footnote
Metals like aluminum are typically used in cold chamber processes.
96
What is the purpose of **venting** in die casting?
To allow gases to escape during the injection of molten metal.
97
Fill in the blank: **Die casting** is often used for _______ applications.
Consumer products
98
What is a common defect in **die casting**?
Air pockets or voids can occur if venting is inadequate.
99
Define **gravity die casting**.
A process where molten metal is poured into a mold under the influence of gravity.
100
Define **single crystal**.
A solid material where the crystal lattice is continuous and unbroken throughout.
101
What is the **benefit** of single crystal production?
Improved mechanical properties and performance in high-temperature applications.
102
True or false: Single crystals are used in **semiconductors**.
TRUE
## Footnote
Silicon wafers are often single crystals for electronic devices.
103
Fill in the blank: **Directional solidification** is a method used in _______ production.
single crystal
104
What is the **Czochralski process**?
A method for growing single crystals by pulling a seed crystal from molten material.
105
Define **metal casting**.
A manufacturing process where molten metal is poured into a mold to solidify.
106
What is the purpose of **molds** in metal casting?
To shape the molten metal as it cools and solidifies.
107
True or false: Sand casting is a common method for **metal casting**.
TRUE
## Footnote
It's widely used due to its cost-effectiveness and versatility.
108
Fill in the blank: **Alloying** is the process of mixing a metal with _______.
other elements
109
What is **investment casting**?
A precision casting process using a wax pattern to create complex shapes.
110
Define **die casting**.
A metal casting process that forces molten metal into a mold under high pressure.
111
What is the main advantage of **die casting**?
High production rates and excellent dimensional accuracy.
112
True or false: Metal casting can only be done with **ferrous metals**.
FALSE
## Footnote
Non-ferrous metals like aluminum and copper can also be cast.
113
What is the **lost-wax casting** technique?
A method where a wax model is melted away to create a mold for casting.
114
Fill in the blank: **Cooling rate** affects the _______ of the cast metal.
microstructure
115
What is **shrinkage** in metal casting?
The reduction in volume of metal as it cools and solidifies.
116
Define **porosity** in cast metals.
The presence of voids or holes within the solidified metal.
117
What is the role of **flux** in metal casting?
To remove impurities from the molten metal during the casting process.
118
True or false: Single crystal casting is used in **aerospace** applications.
TRUE
## Footnote
Single crystal turbine blades enhance performance in jet engines.
119
What is the **solidification time**?
The duration it takes for molten metal to cool and solidify in the mold.
120
Define **surface finish** in castings.
The texture and smoothness of a casting's surface after manufacturing.
121
What affects the **internal quality** of castings?
Factors include material composition, cooling rate, and mold design.
122
True or false: A rough **surface finish** improves corrosion resistance.
FALSE
## Footnote
A smoother finish typically enhances corrosion resistance.
123
Fill in the blank: **Porosity** in castings refers to ______.
The presence of voids or holes within the material.
124
What is the purpose of **finishing processes**?
To improve surface quality and dimensional accuracy of castings.
125
Define **casting defects**.
Imperfections that occur during the casting process affecting quality.
126
True or false: **Sand casting** produces a better surface finish than investment casting.
FALSE
## Footnote
Investment casting typically yields a superior surface finish.
127
What is **cold shut** in casting defects?
A defect where two streams of molten metal fail to fuse.
128
Fill in the blank: **Shrinkage** occurs during ______.
The cooling and solidification of molten metal.
129
What is the role of **mold materials**?
To shape the molten metal and withstand high temperatures.
130
Define **machinability** in relation to castings.
The ease with which a material can be machined to desired specifications.
131
True or false: **Surface finish** does not affect the mechanical properties of castings.
FALSE
## Footnote
Surface finish can influence fatigue strength and wear resistance.
132
What is **surface roughness**?
A measure of the texture of a surface, quantified by the average height of irregularities.
133
Fill in the blank: **Defects** can be classified as ______ or ______.
internal or external.
134
What is the significance of **heat treatment**?
To enhance the mechanical properties and internal quality of castings.
135
Define **finishing techniques**.
Processes like grinding, polishing, and coating to improve surface finish.
136
True or false: **Internal defects** are visible on the surface of castings.
FALSE
## Footnote
Internal defects are hidden and require non-destructive testing to detect.
137
What is **casting simulation**?
A computer-based method to predict casting behavior and defects before production.
138
Fill in the blank: **Surface treatments** can enhance ______ properties.
Corrosion resistance and wear resistance.
139
What is the impact of **cooling rates** on castings?
Cooling rates affect grain structure and the likelihood of defects.
140
Define **porosity** in sand casting.
The presence of voids or pores in a casting, leading to reduced density.
141
What causes **gas holes** in sand casting?
Gas holes are caused by trapped gases during the solidification of molten metal.
142
True or false: **Porosity** can weaken a casting.
TRUE
## Footnote
Porosity can lead to structural weaknesses and affect mechanical properties.
143
Fill in the blank: **Gas holes** are often caused by _______ in the mold.
moisture
144
What is the effect of **moisture** on sand casting?
Moisture can produce steam, leading to gas holes in the final casting.
145
Define **shrinkage porosity**.
Porosity that occurs due to the contraction of metal as it cools and solidifies.
146
What is a common method to reduce **porosity**?
Improving mold design and using drier sand can help reduce porosity.
147
True or false: **Gas holes** are visible on the surface of the casting.
TRUE
## Footnote
Gas holes can appear as small pits or voids on the casting surface.
148
Fill in the blank: **Ventilation** in molds helps reduce _______.
gas entrapment
149
What is the role of **core** in sand casting?
Cores create internal cavities and can influence porosity levels.
150
Define **blowholes**.
Blowholes are large gas holes that form when gas is trapped during solidification.
151
What is the impact of **temperature** on porosity?
Higher temperatures can increase the likelihood of gas formation and porosity.
152
True or false: **Sand quality** affects the porosity of castings.
TRUE
## Footnote
Using high-quality sand reduces defects like porosity.
153
Fill in the blank: **Additives** can be used to improve _______ in sand casting.
mold strength
154
What is the significance of **mold permeability**?
Mold permeability affects gas escape, influencing porosity and gas hole formation.
155
Define **surface defects** in sand casting.
Surface defects include imperfections like pits or roughness caused by porosity.
156
What is a **defect** in casting?
A defect is an undesirable feature that affects the quality of the casting.
157
True or false: **Proper cooling** can help reduce gas holes.
TRUE
## Footnote
Controlled cooling rates minimize gas entrapment and improve casting quality.
158
Fill in the blank: **Degassing** techniques are used to remove _______ from molten metal.
dissolved gases
159
What is the purpose of **mold coatings**?
Mold coatings can reduce gas absorption and improve surface finish.
160
Define **inclusions** in sand casting.
Foreign materials trapped in the casting, leading to defects.
161
What causes **hot tears** in castings?
Rapid cooling and contraction of metal during solidification.
162
True or false: **Cracks** can occur due to thermal stress.
TRUE
## Footnote
Cracks often form when the cooling rate is uneven.
163
Fill in the blank: **Inclusions** can be caused by _______ contamination.
Sand
164
What is a common source of **inclusions**?
Oxides, sand particles, or other foreign materials.
165
Define **cracks** in the context of sand casting.
Fractures that occur in the casting due to stress or cooling.
166
True or false: **Hot tears** are only found in ferrous metals.
FALSE
## Footnote
Hot tears can occur in both ferrous and non-ferrous metals.
167
What is the effect of **inclusions** on mechanical properties?
They can weaken the casting and reduce its durability.
168
Fill in the blank: **Hot tears** are associated with _______ solidification.
Uneven
169
What is the primary prevention method for **inclusions**?
Improving material cleanliness and control during pouring.
170
Define **hot tears**.
Cracks that develop in a casting due to thermal stress.
171
True or false: **Cracks** can be repaired after casting.
TRUE
## Footnote
Cracks can sometimes be welded or filled, but may affect integrity.
172
What is a common method to reduce **hot tears**?
Controlling the cooling rate during solidification.
173
Fill in the blank: **Cracks** can be minimized by proper _______.
Design
174
What role does **mold design** play in defects?
Poor mold design can lead to increased inclusions and cracks.
175
True or false: **Inclusions** are always visible on the surface.
FALSE
## Footnote
Inclusions can be internal and not visible without inspection.
176
What is the impact of **inclusions** on casting performance?
They can lead to failure under load or stress.
177
Fill in the blank: **Hot tears** are often a result of _______ cooling.
Rapid
178
What is one way to inspect for **inclusions**?
Using non-destructive testing methods like X-ray.
179
Define **defect** in sand casting.
Any imperfection that affects the quality or performance of the casting.
180
Define **shrinkage cavity**.
A defect in cast metal caused by contraction during solidification.
181
True or false: **Air pockets** are caused by trapped gas during casting.
TRUE
## Footnote
Air pockets can weaken the structural integrity of the cast.
182
What is a **cold shut**?
A casting defect where two metal streams fail to fuse properly.
183
Fill in the blank: **Shrinkage cavities** often occur in _______ sections of a casting.
Thick
184
What causes **air pockets** in casting?
Trapped air or gas during the pouring process.
185
Define **cold shut**.
A defect resulting from insufficient heat at the joint of two metal flows.
186
True or false: **Shrinkage cavities** can be eliminated by increasing pouring temperature.
TRUE
## Footnote
Higher temperatures can help reduce the volume of shrinkage.
187
What is the main effect of **air pockets**?
They create weak spots in the casting, compromising strength.
188
Fill in the blank: **Cold shuts** can be prevented by ensuring _______ flow.
Continuous
189
What is a common solution for **shrinkage cavities**?
Using risers to provide additional molten metal during cooling.
190
True or false: **Air pockets** are beneficial for casting strength.
FALSE
## Footnote
Air pockets weaken the final product and should be avoided.
191
Define **casting defect**.
Any flaw that occurs during the casting process affecting quality.
192
What is a **risering** technique?
A method to supply molten metal to compensate for shrinkage.
193
Fill in the blank: **Cold shuts** are often visible as _______ lines.
Wavy
194
What type of casting defect is a **shrinkage cavity**?
A volumetric defect due to solidification shrinkage.
195
True or false: **Air pockets** can be detected using X-ray inspection.
TRUE
## Footnote
X-ray can reveal internal defects not visible externally.
196
What is the primary cause of **cold shuts**?
Insufficient temperature or velocity of molten metal.
197
Fill in the blank: **Shrinkage cavities** typically form in _______ areas of a casting.
Thick
198
What is the impact of **air pockets** on casting performance?
They can lead to reduced mechanical properties and failure.
199
Define **defect** in casting.
An imperfection that affects the integrity or performance of a casting.
