Introduction to the Science and Engineering of Materials
Introduction to the Science and Engineering of Materials MSE 2090
Popular in Course
Popular in Materials Science Engineering
This 13 page Class Notes was uploaded by Jamison Kirlin on Monday September 21, 2015. The Class Notes belongs to MSE 2090 at University of Virginia taught by Leonid Zhigilei in Fall. Since its upload, it has received 18 views. For similar materials see /class/209593/mse-2090-university-of-virginia in Materials Science Engineering at University of Virginia.
Reviews for Introduction to the Science and Engineering of Materials
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 09/21/15
m mania Chapter Outline Phase Diagrams Microstructure and Phase Transformations in Multicomponent Systems De nitions and basic concepts Phases and microstmcture Binary isomorphous systems complete solid solubility Binary eutectic systems limited solid solubility Binary systems with intermediate phasescompounds The ironcarbon system steel and cast iron N02 tested 812 Th2 Gibbs Phase Ruiz De nitions Components and Phases Component chemically recognizable species Fe and c in carbon steel H20 and Nacl in salted water inary alloy contains wo components a ternary alloy 7 three etc h e 7 a portion of a system that has uniform physical and chemical characteristics distinct phases in a system have distinct physical or chemical characteristics er and 39 e and are separated from each other by definite phase boundaries A phase may contain one or more components systems Wlth we or more phases are mixture heterogeneous systems A singlephase system is called homogeneous 39 t s o m mansaur D e niu39on s S olubility Limit Solvent host or major component in solution solute minor component chapter 4 Solubility Limit of a component in a phase is e maximum amount of the component that can be dissolved in it eg alcohol has unlimited solubility in water sugar has a limited solubili oil is insoluble The same concepts apply to solid phases Cu and Ni are mutually soluble in any amount unlimited solid solubility while c has a limited solubility in Fe Microstructure The properties of an alloy depend not only on proportions ey at the microscopic level Thus the microstructure is specified by e number of phases their proportions and eir arrangement in space lit This is an alloy of Fe with 4 wt c There are several has The long gray regions are akes of graphite The matrix is a line mixture ofBCC Fe and FeZC compoun Phase diagrams will help us to understand and predict microstructures like the one shown in this page u w v incmincu39nn tn Materials Science chapter 9 Phase Diagram Equilibrium and Metastable States A system is at equilibrium if at constant tempemture pressure and composition the system is stable not changing with time Equilibrium is the state that is achieved given suf cient time But the time to achieve equilibrian may be very long the kinetics can be slow that a state along the path to the equilibrian may appear to be stable This is called a metastable state In thermodynamics the equilibrium is described as the state of that corresponds to the minimum of errnodynamic function called the free energy Thermodynamics tells us that Under conditions of a constant temperature and pressure and di 39 composition the ection of any spontaneous change is to gy The state of stable thermodynamic equilibrium is the one with minimum free energy A system at a metastable state is trapped in a local minimum 0 free energy that is not the global one equilibrium Free Energy metastable Univu39sity nl39Virgjnia Dept er Materials Science and Engineering 5 incmincu39nn tn Materials Science chapter 9 Phase Diagram Phase diagram A phase diagrams show what phases exist at equilibrium and what phase transformations we can expect when we change one of the parameters of the system T P composition We will discuss phase diagrams for binary alloys only and will assume pressure to be constant at one atmosphere se diagmms or aterials with more than two components are complex and dif cult to represent Univu39sity nl39Virgjnia Dept er Materials Science and Engineering 7 intruductjnn tn Materiais Science chapter 9 Phase Diagram Phase diagram phase diagram a hical representation of the combinations of temperature pressure composition or other varibles for which speci c phases exist at equilibrium For H20 a typical diagram shows the tempemture and pressure at which ice solidwater liquid and steam gas exist 39 suu urni intruductjnn tn Materiais Science chapter 9 Phase Diagram Binary Isomorphous Systems I Isomorphous system 7 complete solid solubility of the two components both in the liquid and solid phases J 39Im punt hree phase region can be identi ed on the phase diagram iquid L solid liquid or L solid or Liquidus line sepamtes liquid from liquid solid Solidus line separates solid from liquid solid T L Univu39sity nl39Virgjnia Dept er Materials Science and Engineering 8 an m mm m mm Cu in m m m m m W n mum min mummy in my W91 mum Iymm cum n WWW n m m um 1m mumm am 1 m n numme quotmunm W91 yum mumumu mm m nwz mayquot 1 mwmmmmmmm 2 m n lntrnrlllctjnntn Materials Science chapter 91711 Diagram The Lever Rule nL it Effquot 3quot quot39 f x e in Mass fractions WL S RS Cu Co Cu CL Wu R RS Co CL Ce CL Univu39sity nl39Virgjnia Dept pr Materials Science and Engineering 13 lntrnrlllctjnntn Materials Science chapter 9 Phase Diagram Derivation of the lever rule 1 All material must be in one phase or the other wu wL 1 2 Mass of a component that is present in both phases equal to the mass of the component in one phase mass of the component in the second phase wmcbc WLCL c o 3 Solution of these equations gives us the Lever rule WL Ce Co Ce CL We Co CL Cu39 CL Univu39sity nl39Virgjnia Dept pr Materials Science and Engineering 4 lntrnrlllctjnntn Materials Science chapter 9 Phase Diagram Phase compositions and amounts An example co 35 wt cL 315 wt cm 425 wt Mass fractions WL Cu Co Cu CL 068 Wu CoCLCuCLO32 Univu39sity nl39Virgjnia Dept pr Materials Science and Engineering 15 lntrnrlllctjnntn Materials Science chapter 9 Phase Diagram Development of microstructure in isomorphuus alloys Equilibrium very Slow cooling 1 223 2 z zigzag 51 quotr 1 5 E i 5 1 555 3 53 5 i mmiiirnnuilg F i mqu Kymm waywin hmwm wwwmqu mman mmmmmm mmmmmmm m nmmm mm mmmcm mmrmrmyemnh mman Mummm mm w mm W wm 8 E 2111 mm M w m w m m mnnmunmmm mnmmxmm mommam rmmmm mmm 49 alumniyum WNW mmmnC m mmmm mm allay m mum Mmpmum mwmmn mmm 1m an mummmam an munm u mwmumqmmm unlyavafwynnm nun mmmm Km FanunmelllVdVyZ Mm wwwm mmquot Wm m xMu mm 91 39 mm m y a m M m 7 cm g mm LuuLvu 53 mu n3 mumm w ix WW I WNW m w m m mAl u s my n m pun w v Mm a a 1 my a w nu ma quot4 u m 14 cm munmum w wasnmmuuum n hwuuhv n my M1 Imuka 1 uim I Euletluil Reulhns u The shave phase ahagxam euhmhs hmh an summit 13932th and its suhasaue sham an eutectmd 13932th Periletlic Rncl39nns peaneeeie heaehahe sahd phase and hqud phase wx tag hex m a secmd sand phase at a pamema temperature and campasmm hpm esahhge e g L EH slaw farm at 39he bvundary between 39he m reacting phases 39hu sepahauhg them an a slawmg dawn my further reachan system Lhatwe wxll Carma115121 Cung39llenl Phase Tnnsfumz nns A esnmem mnsfumzl39nn mvnlves ha change eh empasushe g allmxapxc kansfarmauan such as we u we ah melung uahshahs m pure sshas Fax an meahguem kansfmmauan at least me phas changes campasmm 2g emeeue emectmd pemeeh reacuans men Cungmenl making an The hunJmn Czrhide heme Phase magma h then amplest farm steels are ansys af Imn Fe and CarbmC The Feec phase aagam xs aramy samplex hp ta ammd 7 c ahhsh aquot W may m and y mn uw nmun m n mam w y W n mm 721 c mum c Wmmm non m mum vu lmymn hummmu mab Amnmmmnw q N crnslnlculre nf Eutectnid Steel 11 allay uf eutectmd m m c sluwly it farms 2 m c alums between femte n nzz Wm pearllte has pmp mles lmemealaze bntde cemenme N crnslnlculre nf hypnmltectnid Steel 1 hypnzlltecmid 12 than emectmd Greek alluys 1 0H1 gt mFeJc l 4 N crnmncmre nf hypnentectnirl Steel 11 Hypueutectmd alluys Bantam pmsutectmd femte farmed Mcrnmucmre nf hypermltectnid steel 1 that eumam eutectmd femte and cemenme Pearllte Proeulecloid l F930 Eulecloid l u 1 gt 1FeJC gt mule hyperumamiid 33931 11 Hypexemzc md a ays camnm pmeutzctmd cemznmz Pearme l camnm emectmdfemm mdcememm Hawm calculate m relative ammlms armemma phase a Dr hp and puln Examplz faxhypxemecmlda aywnhcampusnmn c Fnctmn afpearlne xvx 7 7 c57 415 Fnctmn afpmemecmxd cemenmz wm Vvx cn1sm 415 Sunnmry Mm sure yml mdzmmd languge mdcancep39s gt Amenquot gt Cement gt Campamm gt Cangmm murman Eqmllbnnm Fem e gt Hypexemzc md allay gt Hypaemecmxd a ay gt Imumzmhc campmmd gt human pmm gt Mmcmnmm gt mum gt Penman nactmn gt Systzm gt Tennmalsalld salutmn gt m hm
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'