Question:
The following tabulated data were gathered from a series of Charpy impact tests on a commercial low-carbon steel alloy.
Temperature(∘C)50403020100-10-20-30-40Impact energy (J)76767158382314951.5
(a) Plot the data as impact energy versus temperature.
(b) Determine a ductile-to-brittle transition temperature as the temperature corresponding to the average of the maximum and minimum impact energies.
(c) Determine a ductile-to-brittle transition temperature as the temperature at which the impact energy is 20 J.
Answer:
a) see the attached graph
b) max E = 76 and Min E =1.53 average = 77.5/2 = 38.75 J
this corresponds to about 10° C
c ) at E = 20 J temperature is about -2°C
Answer:
Bridge
Explanation:
A common, simply bridge truss is the zigzag.
Answer:
to make the bace of a building more sturdy
Explanation:
example: the bace of the empire state building is stone very sturdy
Answer:
metals, composite, ceramics and polymers.
Explanation:
The four categories of engineering materials used in manufacturing are metals, composite, ceramics and polymers.
i) Metals: Metals are solids made up of atoms held by matrix of electrons. They are good conductors of heat and electricity, ductile and strong.
ii) Composite: This is a combination of two or more materials. They have high strength to weight ratio, stiff, low conductivity. E.g are wood, concrete.
iii) Ceramics: They are inorganic, non-metallic crystalline compounds with high hardness and strength as well as poor conductors of electricity and heat.
iv) Polymers: They have low weight and are poor conductors of electricity and heat
Answer:
• Corona discharge means <u> </u><u>neutralization</u><u> </u><u>of</u><u> </u><u>charge</u><u> </u><u>action</u><u> </u><u>at</u><u> </u><u>a</u><u> </u><u>sharp</u><u> </u><u>point</u>
example; a pear shaped conductor, lightening conductor, van de graaf generator.
Explanation:
• In corona discharge, When a sharp conductor is placed somewhere in open space. The charges of opposite chrage attract the opposite ions in the air around that conductor.
• This increases the charge density and electric field intensity at the sharp point, this neutralises the charge at sharp point hence a discharge known as corona discharge occurs.