{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Midmester Solutions_2007

Midmester Solutions_2007 - AEROSPACE MATERIALS...

Info iconThis preview shows pages 1–14. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 8
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 10
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 12
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 14
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: AEROSPACE MATERIALS LABORATORY (ASE 324L) Spring 2007 Mid Semester Quiz March 21, 2-4 p.m., BUR 106 Please attempt all four questions. The points assigned to each question are shown in ( ). This is a closed notes/homework/book exam. Space for your answers is provided in this booklet. NAME: Section (circle one) T W Th F 1. The tensile stress-strain curves obtained from two carbon steel specimens are shown below. The specimens had initial gage lengths and diameters of 4 and 0.5 cm respectively. (a) Describe how you would conduct the experiment from which the data was obtained. Indicate how the experiment would be controlled, what measurements would be made and identify the properties that could be obtained from the data. What additional data is required to determine Poisson’s ratio? (4) (b) Identify the two materials (i.e. material A & B) and determine their Young’s modulus, yield strengths and ductility. (9) (c) The Poisson’s ratio of material A is 0.33. Determine the change in diameter of the specimen at the onset of yielding. (2) (d) In material A, identify what is happening prior to necking and determine that plastic strain at the onset of necking. (2) (e) In material B, identify what is happening during the constant stress phase and determine the change in length of the gage section during this time. (2) (t) The two carbon steels have the same carbon content explain why some of the properties in (b) were the same and why other properties differed. (6) Axial Sh'a'n 0.05 0.10 0.15 0.20 __.—— _’~ Axial Slra'n 0.05 0.10 0.15 0.20 500 ... ............ “.m— TlfiTTT“ ”WNW?“ Stress a (MPa) . 640 600 540 «w ' 200 I | l I l l | l l 0 0.005 0.010 0.015 0.020 - 0.005 0010 0.015 0.020 Axial Shah Axial avail Bf. _111_—————11..1wm1_~11___1111_111__111 l TLo-Mda-{n _fliLLAQ-gé. _‘gw _{gjclc gig-Mes v; 01me 441011.. .111-.1.1._.A,111_11_..___11111 _11 ___..1-11._.1_1_1_. .1111 1—1 11111. 111 1 1_1_____1_.__11.11_...11_.__1 114).. gees-(£625-.. 2% M5£111 .- 11.11-- -1- 1.1-1.11 11 1....- 1-1-- .--11111 .- MGM“ 11°me aMJ ”(0,4, 4mm” M-SUL- «o! . 6‘4”"va nicer-1511212251. 11:15:11 -. - . 11-11F5124E1g11, 03:51, i: (16045111 111$- +°V~3L fits-$11. ,1....-...--_--------_11_ .11... 1 .1- 111111115.“ 5.612.25- 21.015522: 5152:1521 1.2-7:- Z-ff/1‘61111 -- -....-1--- .1 - 1-2)..- Nco-‘rmw‘ A. :.-- Mix-215.514.19.321 -22 2322221.. {2122111121411 11 ‘ “640%! g ‘ (40+ vofleJ 5(13‘ 1 111.1,. 1.11.11-11.11. 1., m 1.- .1 1- .1 1.1 .11. m.~~1~w~~m ___1_1111..11_ .11... 1111111.. 1.111.11....11..1_._--.1.-11 11.111111111111111...— WV1.1:.-:.11424A.f....11:i...""."fi’.'-'T_" 211151111 5 _1.....11:1: - - 1’: Wait“: .1 - - 1; 50‘6" -1111... 1 11 .- 1 .. E - 0.1.9251 i 200 ‘3?“ E: 2759-12-1; 2-00 11‘;- - -1- 1111 03590011611 - O?“- ‘00 “(a 1 6., = 5110qu .1 1,.1111. 1 .11111...111..1.11.1...1.111 111 1-. 11.111 111.111.111.11... .11 .-. -1. 1.... 1 11.1.1 1. . 1 11,1. .- 1 1.11....1..111..11- 11- 1.. 1.... 11.111 .1. _11..1_1_...1 1.11... 111.111....- 111111111 1 1111111,.- ..1.- 1,111.11... 11-111111111111111.“ 11- . 1. £11-... . Qt-.. - 1-H:- -.f.9-1'-9191§-1 . 1 .1. ‘12211 21-15-15.- . E 59‘ . 1-11.1- 1-11-1- m'elu a. M} '-' 7—02“ d = “Ogéxo 005x05 _cw. ’1 . . . [/4 .1.ata- 1.1-1.1..1-1 ., 1.1.1.1- .1-11-111111... 17 11-11141. . . ., .111. 1.. w 1.1111 1.1....111- 111 11..1...11-11.....1..11-111111. ._ - .E ‘ 9. 0 92 5.- 1-2": 1- 4) Th! Mock; (AL (.59 Sham IAwd-eu HA; :DtclOCafiOueu+au3’-emp1+ Maui; [to Makfllnu S‘H‘eSQ’ [99C[ 1‘6qu +9 Moo: GeslococI-w S _- ToJrqlsham ad neck is .0, 9?. q EH51“ fi-mw‘ .. 3e— 0/6 E 5:13:19“ 1 0 DOS . {e 5‘ pie ~59 Q 05;; 1-1L L6),,__, \akau_£¢ 10:1 1; Jug ,‘l-o __M¢,_§ 12454 ae 1,1461x1aflv ghmu Aé‘ p- Clo-<9 .003 1: o QIZW 1.1.11.1-.. 11.1 -11.. ..,_1......, .1 . .1......1._.A.1...1111._._._....- §1,-,:::E: Z444 s, 1,, 1.1%, ‘14 41262244 .44174,,““2.4:: _---_._. Q Q ,. . ,. ., 1,:-91.,2é1‘é-17,-.Q11éimm. ,1 :1: 111.111.191.111; 1911191, 2&1 M M- ,1--- 1111.51.61 -1L1g21me veggiflgmfl 1, attain {calla—1% [voyeuésf 4:9- <49ch! 1...... 626 l/las sham ’AwJ-emcaq eQA-LQ +0 dQSIDca-Hovx walewh—E 1.1.1.11..1.1.-..1..1—_— -11‘... .1-.. .1. .1.. 1.....-11... .1. .1 ...1_.._.1 “11......” ..._1-1..- ..—_.111111.1.11.11 1.1.1.11. 1...... _.-_. ............1... 1.11__ .1. .1,...1.1..111.—-1-..¢1..~.-1»11- 5 Black 49; 99‘1““ cue 4a” (We _- do 1404' IOKUOCLIC , obslocwhou mouewedfi ~~mw~wfl ‘C 2; ‘1‘;&$ A “alum » x/(JJJ ghetfifln gaunt +0 £15 WW .1 .-._1., ..1.-.111.-_..1.,. ...,- 1—14.-- . 11..-. ....-..1....11 1 .1 ,, ,. ,, ,. WOV%.M1%j11 Q, _Q 1125 111., 1 1.31.. 111.1117 11.1... 11.11 11.111 QQQQQQQQ‘Q .. 1 10??“ {PM {'7’ goo-t , filecg’mu ,mgye M 2. A portion of the carbon steel phase diagram is shown below. The large circles enclose schematics of the microstructure. The carbon content (by weight %) at the points N and O is 0.022%C and 2.14%C, respectively. The carbide single phase field has its boundary as a vertical line at 6.7%C (outside the scale of the diagram). (3) Identify the phase fields in the phase diagram by writing your answer in the dashed circles or ellipses. (4) (b) Identify the eutectoid composition and temperature. (2) (c) An alloy with a composition 0.27%C is slowly cooled from the point y to c. Identify the phase of the grains in the schematic (large circle) associated with point c. (2) (d) Determine what phases are present at d, their compositions and relative amounts. Identify the phases in the grain structure schematic and their development as cooling proceeds to e. Assume that cooling was sufficiently slow to form the equilibrium structure. (6) (e) Determine what phases are present at f, their compositions and relative amounts. Identify the phases in the grain structure schematic. Assume that cooling was sufficiently slow to form the equilibrium structure. (6) (f) Suppose the alloy had been quenched from y to room temperature. With the help of the TTT diagram (over), indicate what phases are formed as the cooling rate decreases from a very fast quench to a very slow cool. (5) Temperature PC) Co Composmon (wt% C) WLWLW2W-WWQLW1L X LIL: Fe WWLCLLLYLWQLQLWOL+ F€;.QW_ C55": flame) .. .. W W Lima, 4 .3 af Co (<2 21,-: 2}, a)” ,‘L,,'LW_._ . w... W_._W.WW.WWW.-L._WTTW ..WW_ _.,_ W.-. _. WWW- ”..-—WW“... L out; a; was LLMQBW at g .. , , Q: W ,ifibfix: ,W W “*I~WWW __ W, A, W --....WWW- L Lamp osihoias WW ..W,Co<__=W,_._W2/30 ‘, ‘95 01. _. NW “HIM Q;l:g+we aMougL 17,5? ”110;: L107: W ' fix”: Wm“: 60%: __ MW howcu‘azg, Y 0"“ 0» «Ci/u flim- (noMJafas. _L¢) m ~~~~~~~~~~~~~~~~~~~~ “QM” 91%;“ L, ngW: WWLLSL 94’ A; 7%,; ‘,:WVQILWLM9\ rad-ts Ac VLo_'(’ allow 1— ol+F€$C L (inshbje I fawn; ~ ~r~ M Macaw?“ 4;,” L ML L b1: 35? _C NOJkHél‘l'e 11$ “MPERIY AN‘Q L A9 [0M3 asidoafwua vac‘c MtQC-es 1:Ln_ nose _ WI‘I'CMStk \c gamed}. , W“ 1“” . w, .. ., ,w -,,, WWW”, ,W._,,,_W__,_W_W.,,___W, ._ ,, _ '1’ -TBLAJHQ b»£fl.§.‘l¥§.§£,bm‘fi’ «M4158: 19mm- _._ _ __ __ W WWW/$94 49ng L01: EWCWL W ,_ _ W _ WW W- _. W- :4 “VI/'17, DM 4 ‘ 33% 2‘ v, rig/0% 3. The hard ball models below represent three common atomic arrangements in metals. (a) Define each one. (3) (b) Sketch the unit cells for (i) and (ii) and indicate how many atoms are contained a unit cell. (4) (c) If the atomic radius of the element in (i) is 0.140nm, determine the size of its unit cell. (4) (d) Make a sketch of an edge dislocation and indicate how the dislocation line moves through a crystal when a shear stress is applied. (4) (6) Describe two ways in which dislocations can be created in a material. (4) (f) Explain how solution and aging treatments in aluminum/copper alloys can be used to strengthen the material. (6) 5e) Disbcafiegmgw Wigs: “MIA wwwwwwwwwwwwww Wm @LLSIWQW'I'W“ MCNLY ($ HO'I’ 96L c,_(___em++o +°.<1<—°0‘1-‘I’ - .. éfl‘f DIM GUMOWTWQé 95.40. ¥-£.1919§¢.'¢._4€ M91512; ’ébaf ..__ ...0¢¢CM¢rS “130119 also Maw 404w?_j&ac091.c‘ _. ,_ ..-Ft.6td€‘eecu New T‘. W) .. W a .«o . .‘n. .— ‘_ _. ~ .¢ b... ... ~ .0“. W «~— ~.... .— 4 I“ b équ-I'wM 'I'I-ccd’md WLVOIueS- «Wen 4W “, g; Phase -, Cu Is 'I-ca‘olon OCI E T _ Cguau'I-ya‘I'IOI/I . I9 ({- /O V}, 0 IA .- MN W chbcq—vag 9:6. I‘aIeEfieI .121 went“ Corfu ., ... AQIFACA “(Lalowwui cfuucla NaILows 'énMaI-uu at! , @4421th flaw ms Q'f 8’ 9494 I9. wsTL 1046499ch W” afaew‘c} ‘I’MMe TI/gauwcvosIIfuc‘I't/U‘CS aged cflLheoothw-v WW 8” C: P 3.05432; CumeMS 'TT ' @3343. cu iv.“ " § [7' was $54431; P 4. A steel rod is suspended from one end in a high temperature environment. There is a concern that it will creep under its own weight. The stress in the rod is given by 0' = pgx , where p is the density, g is the acceleration due to gravity and x is the distance from the bottom of the bar. (a) The secondary creep rate of the rod material is given by és = Acme—9”". Define the terms in the expression and indicate how you would obtain all the material constants. (8) (b) A creep test at a stress level of 1MPa and 527°C has determined that the exponent, activation energy and secondary creep rate of the material were 4, 200kJ/mol and 1x10'7/s, respectively. The universal gas constant is 8.31J/mol/K. Determine the creep behavior of the material. (4) (c) The rod is 0.5m long, its density is 7.7x103kg/m3, and its Young’s modulus is 210GPa. How many days would it take the end of the rod to displace lum at 627°C? (8) (d) The Larson Miller parameter is T (C+log tf). Define the terms in the parameter and describe how it is used to link accelerated test data obtained at different stress and temperature levels from anticipated flight conditions. (5) Note: In (c) you will need to recall that the displacement at any point in the rod is u = Iadx , where a is the strain. WWWQWWQ: ..4 Occh +Iwe_ dewflwj Wflflfiz W‘PWWV‘. 0642+ 4-9 caud'qu 44444294944411.94444949929934 99904 4 .4 64444 22:2“ 'f4f44.:4444444444 444. 4.444. 4-4 4W, 4. , _W 4 44 44 4 -44 4 4 W 444 444 44444 gigs (qTfiM>‘f"‘-\4 W 4.4 4 444.. m 4 4 ‘i44A 29:42: aee 4 4452+: we “6114344- «x/‘_Y\ quh4fiQJ/4‘fi'44444i1443dgfkwT M vuiw-g O“ fijwe‘lwmq, Wig? Q 4.44:. acfiua‘swu Win! gmgwe? hx O'cml vcuj T +1 2 4 99922112244"? 99992994 44 +1 A. —:_ “9+9 «1 4499.99199L 44949 494499 29 +2992 29» -4.-. W 44¥+X4+2~ EwgagLé -4444 bl 4c: ’44. meg 44. T 627 c 900KML+ f. 4444. .44.,44444 G :. 340° 4‘443/“0‘ 26:4}‘67/9 44 “ , ,. LL.— M _.,_,,_.~M_._~ WM. -4 a-..“ m. Mm.“ . “i. -m ‘.___-~ M M 5- u sx.;9;-: sum 3 t- _______ _ _ ......... :1-..“ 1:2}: W ___ _~-_P___#_m _ H 2 3%3/2 + New) 6‘63“ ,j_,‘,'_:"";__t:—_wd one ptaawefi " 8 L 1:5 03" £24 V M“. ‘ ...
View Full Document

{[ snackBarMessage ]}