Georgia Lyall Flashcards
What is the principle of heat treatment?
changes the metal’s properties to the specific needs of the use. This is done by heating to a temp range, and hold for a cetian time. Then cooling in air,water or oil.
What is the Rockwell Hardness Test?
Rockwell hardness test measures the the max amount of damage that occurs under a large load by the form of an indent.
How is the Brinell Hardness Test conducted?
In the Brinell Hardness Test, a hard steel or carbide ball is pressed into the material, and then you measure the diameter of the indentation it leaves behind.
What distinguishes the Vickers Hardness Test?
Vickers hardness test uses a diamond pyramid indent and measures the length of the indent.
What does the Charpy Impact Test evaluate?
This message the energy absorbed by the material when a fracture by a swinging pendulum.
What is the Drop Weight Impact Test?
This test is demonstrated by dropping the item from a known height and it demonstrates the impacts.
What is annealing in the context of heat treatment for ferrous metals?
Annealing involves heating ferrous metals to a precise temperature and holding the temperature for a set amount of time then cooling it down slowly in a contorlled temp in a furnance
How does normalizing differ from annealing for ferrous metals?
annealing allows the material to cool at a controlled rate in a furnace.
Normalizing allows material to cool by placing it in a room temperature environment
What is hardening? (ferrous metals)
Hardening is heating the the metal to a high temperature (in the range 760-1300 C) then rapidly cooling in water or oil.
How do temperature changes during heat treatment affect the properties of ferrous metals?
significantly alter the properties of ferrous metals - like latering tougness, hardness, ductility, and grian strcure size and shape
What is the purpose of heat treatment for alloys
to achieve the desired characteristics such as strength, hardness, durability. This is done by altering grain structure and size.
What is the process of solution heat treatment for alloys?
This treatment involves heating the metal up until it’s in a solid solution and then rapidly cooling it.
How does tempering effect alloys that have been hardened?
This involves heating a previously hardened alloyed to a temperature below the critical range then cooling it.
What is normalizing for steel alloys?
Normalizing steel alloys involves heating them above their critical temperature and then cooling them slowly in air.
What is the process of tempering?
tempering is the process of heat treating a material again but at a lower temp range (usally 80-500 degress c) holding for a low time then cooling slowly in air.
