This set of Metal Casting Multiple Choice Questions & Answers (MCQs) focuses on “Slush Casting”.
1. Which of the following methods of casting is employed for the casting of open and hollow objects like boots, toys, dolls etc?
a) Die casting
b) Continuous casting
c) Squeeze casting
d) Slush casting
View Answer
Explanation: Slush casting is an excellent method for producing of open and hollow objects like boots, shoes, toys and automotive products, such as protective skin coatings on arm rests, head rests and crash pads. This method is very simple and widely used for the production of ornamental objects.
2. Slush casting method always requires automation for the production of castings.
a) True
b) False
View Answer
Explanation: For the long runs, slush casting may require a conveyor system for the production process. But generally, it can be a simple handle operation for limited production of castings. So conventionally the work and almost all the operations are performed manually to make the process economical.
3. In slush casting, the method of multiple pouring leads to the fast production of castings.
a) True
b) False
View Answer
Explanation: In slush casting, one pour and multiple pour methods are used. One pour method in which, finished or semi-finished products can be made by one slushing step and in multiple pour method, number of slushing steps are used for the casting that results into fast production of products.
4. A permanent mould is used in the slush casting with some variations for the making of castings.
a) True
b) False
View Answer
Explanation: Normally a slush casting is produced by pouring of molten metal into an open top permanent mould and then the mould is inverted after the forming of a solid thin layer in the mould. The mould is reheated and the hollow casting is safely taken out from the mould for further processing.
5. Slush casting method is easily applicable to the high melting temperature materials.
a) True
b) False
View Answer
Explanation: The high melting temperature materials such as aluminium and brass cannot be cast easily by slush casting method because temperature of melt can make defects in the mould and casting itself, so low melting temperature materials such as tin, zinc and lead are mainly used in the slush casting process.
6. The thickness of the metallic wall of the mould can be used to determine the wall thickness of the casting part in slush casting.
a) True
b) False
View Answer
Explanation: The wall thickness of the casting part not only determined by the thickness of the metallic wall of the mould, but it can also be obtained by considering the other factors like length of time the mould is preheated, and the amount and type of molten metal are used in the process of slush casting.
7. Porosity in the moulding part cannot affect the casting part in slush casting process.
a) True
b) False
View Answer
Explanation: In slush casting, if porosity is present in the mould part, then it can cause detrimental effects on the casting part such as pin-holing, surface gloss reduction and voids in the casting. So, extreme care should be taken while selecting the die or for the preparation of the same.
8. It is not easy to control the internal geometry of the castings made by a slush casting method.
a) True
b) False
View Answer
Explanation: In slush casting, it is not easy to control the internal geometry of the castings because when the mould is inverted some of the material remains sticks to the solidified wall of the casting, which results into the formation of irregularities at the interior part of the casting, which then requires expensive machining.
9. In slush casting, much of molten metal is wasted during the process of inverting mould.
a) True
b) False
View Answer
Explanation: The material does not get wasted in slush casting, instead this process saves a lot of molten metal by collecting it and that is reused for the other slushing steps. This process makes the casting lighter in weight by saving the molten metal; hence this process is good in an economical way.
10. There is no requirement of any type of cores in the method of slush casting.
a) True
b) False
View Answer
Explanation: In slush casting, there is no need of using any core because the hollow section of the casting is made by inverting the mould, which poured down the remains melt after the formation of a solidified layer at the interior part of the mould. So it eliminates the use of core with achieving the desired nature of hollow part of the castings.
11. Which of the following moulds is used in slush casting, in which mould is broken to remove the castings?
a) Copper mould
b) Iron mould
c) Bronze mould
d) Zinc mould
View Answer
Explanation: Bronze moulds are used in some cases of the slush casting when the better surface finish of the exterior part is required. When the metal hardens, the mould is broken to remove the castings. The inside of each cast retains molten texture while the exterior part is very smooth and shiny.
12. Casting’s strength and other mechanical properties are easily controlled in the slush casting method.
a) True
b) False
View Answer
Explanation: When manufacturing by slush casting, it is very difficult to control the strength and other mechanical properties accurately because of the formation of irregularities at the inside portion of the casting. Properties can be enhanced or improved by providing heat treatment to the metal casting.
Sanfoundry Global Education & Learning Series – Metal Casting, Forming and Welding.
Practice 1000+ Multiple Choice Questions and Answers on Metal Casting and Metal Forming and Welding.