Chapter 13 Flashcards
(92 cards)
Materials engineering
The study of the structure, properties, processing, and performance of engineering materials and the systems interactions.
Materials processing
The devienne and technology through which a material is converted into a useful shape with structure and properties that are optimized for the prosper service environment.
Casting
Liquid flows into and assumes the shape of a prepared container after solidifying
Material removal
Remove selected segments from oversized pieces.
Machining
The mechanical cutting of materials
Deformation processes
Exploit the ductility or plasticity of certain materials to produce a desired shape by mechanically moving or rearranging the solid.
Consolidation processes
Build a desired shape by putting smaller pieces together.
Powder metallurgy
Manufacture of a desired shape from particulate material, can involve casting.
Additive manufacturing or direct digital manufacturing
Includes a variety of processes developed to directly convert a computer drawing to a finished product by a layer by layer deposition of material.
Step one of casting
A container must be produced with a cavity having a desired shape and since (mold cavity) with due allowance for shrinkage. Mold material must withstand high temps.
Multiple use molds
Can be quite costly, but can be used multiple times
Single use molds
Preferred for the production of smaller quantities. Can not be used over and over.
Step 2
À melting process must be capable of providing molten material at the proper temperature, in the desired quantity, with acceptable quality, at a reasonable cost.
Step 3
A pouring technique must be devised to introduce molten metal into the mold.
Step 4
The solidification process should be properly designed and controlled. Shrinkage must not produce voids.
Step 5
It must be possible to remove the cast from the mold. With single use molds they are broken apart and destroyed after each cast, but multiple can be harder to remove
Step 6
Various cleaning finishing and inspection operations may be required after the casting is removed from the mold.
Pattern
An approximate duplicate of the final casting
Flask
The ridged metal or wood frame that holds the molding aggregate
Cope
In a horizontally parted two part mold, the top half of the flask is called this.
Drag
The bottom half of the flask is called this.
Core
A sand shape that is inserted into a mold to produce the internal features of a casting such as holes or passages.
Core boxes
Cores are produced in word metal or plastic tooling and are known as this.
A core print
A feature added to the pattern and is used to locate and support a core within the mold.