Chapter 6 Flashcards
METALS
What are some of the properties that distinguish metals from ceramics and polymers
metals have: high strength and stifmess, good electrical and thermal conductivity and higher density than ceramics or plymers
What are two major groups of metals
ferrous and non ferrous
What is an alloy
metal that has two or more elements (one of them is metallic)
what is a solid solution in the context of alloys
alloy in whihc one of the metallinc elements is dissolved in another to form a single phase
Distingush between a substitutioal solid solution and an interstitial solid solution
Substitutional solid: atoms of the dissolved elemnt replace atoms of the solution elements in the lattice structure. An interstitioal solid solution has extra atomsWhat
is an intermediat phase
When the solubility limit of the base metal is exceeded (there is too much solute in the solution so a part of it is not dissolved)
The copper nickel system is a simple alloy system as indicated by a phase diagram, whiyis it so simple
because it is a solid solutionalloy throught its entire composition range
What is the range of carbon percentages which defines an iron-carbon alloy as steel
0,02% to 2.11%
What is the range of carbon percentafe which defines iron-carbon alloy as cast iron
2.11 to 5%
Common alloying elements for steel
Ce Mn Mo, Ni and V
What are some of the mechanisms byw which the alloying elements other than carbon strengthens steel
by solid solution alloying. Cr, Mn, Mo and Ni increase hardenability during heat treatment, CR and MO improve hot hardness, (Cr, Mo, V) form hard carbides with C which increases water resistance, Vanadiun inhibits grain growth
What is the predominant alloying element in all of the stainless steels
Chromium
Why is austentic stainles steel called that way?
Because this alloy exists in its austentinc phase at room temperature (FCC)
Besides high carbon content, what other element is characteristic of cast irons
siliconi
dentify some of the porperties for which aluminum is noted
low density, hgih electrical 6 thermal coductivity, good corrosion resistance, ability to be alloyed to achieve good strength to weight ratios
What are some noeteworthy properties of magnesium
lowest density, propensity to oxideze, low strength. Can be alloyed and strengthened to achieve goos strength to weight ratios
Most important engineering property of copper
high electrical & thermal conoductivity
What elements are alloyed with copper to form bronze and brass
tin and zing
important applications of nickel
alloying ingredient in steel, plating of steel to resist corrosion, nicklel based alloys for temp. performance
titanium properties
high strength-to-wight ratio, corrotion resistance, hgigh temp.strength
applications of zing:
easy to cast, coating inb galvanized steel, alloyingelement with copper to form brass
alloy by lead and tin
solder
name reefractory emtsals
CV, Mo, Ta, W. REfraactory emeans capacit tio withstand high temp. serice
Noble metals, why
platinum, silve,r gold, copper. They are chenically incactive
