超々ジュラルミン開発の伝統を受け継いで ― 超塑 … Technical Reports，Vol.2 （2015） 43 超々ジュラルミン開発ので超塑性材の研究開発と

UACJ Technical ReportsVol.2 201541

UACJ Technical Reports, Vol.2 2015pp. 41-57

TOPICS

15

50719822003

2013UACJ

1 5

2.1

1906Wilm1907Al-Cu-

18

*

18th Japan Institute of Light Metals Medal

Inheriting the Spirit Cultivated in the Development of Extra Super Duralumin: My Study about Microstructural Control in a Superplastic ESD

Aluminum Alloy

Hideo Yoshida

* 652015345-355. The main part of this paper has been published in Journal of Japan Institute of Light Metals, 652015, 345-355.** UACJ Research & Development Division, UACJ Corporation

42UACJ Technical ReportsVol.2 2015

Mg1909Al-4%Cu-0.5%Mg-0.5%MnDuralumin191019141916Fig. 1UACJ

1919

Cu 4%Mg 0.5%Mn 1.0%192111922419266191644 kg/mm2430 MPa28 kg/mm2

270 MPa 22% 17SAl-4%Cu-0.5%Mg-0.5%Mn192217S250007

2.2

Super-Duralumin19278192817S14SAl-4.4%Cu-0.4%Mg-0.9%Si-0.8%Mn

T649 kg/mm2480 MPa42 kg/mm2410 MPa13%17S1931Mg24SAl-4.5%Cu-1.5%Mg-0.6%Mn24S-T349 kg/mm2480 MPa35 kg/mm2 340 MPa18%17S24S24ST3

Fig. 1 Part of frame of Zeppelin Airship shot down near London, brought into Japan by Japanese Navy and stored in UACJ Corporation 1).


Alclad 24S-T3

1934 SDAl-4.2%Cu-0.75%Mg-0.7%Mn-0.7%Si SA1Al-1.2%Mn-0.8%CuSDC193524S193324S193524SSDSDC24SSA1SA3Al-1.5%/Mn-0.55%Mg193614S24S14ST624S-T324S910193519405

10

2.3

24S11

Fig. 224S1935810Fig. 3No. 175 kg/mm2

740 MPa

Fig. 2Dr. Isamu Igarashi 1892-1986.

Fig. 3 First report on the research of Extra Super Duralumin (cover and abstract) 2).


54 58 kg/mm2 530 570 MPa20 12

193669135036Fig. 460 kg/mm2 590 MPaAl-4%Cu-1.5%Mg-0.5%MnDAl-8%Zn-1.5%Mg-0.5%MnSanderSNational Physical LaboratoryZinc DuraluminEAl-20%Zn-2.5%Cu-0.5%Mg-0.5%Mn Al-8%Zn-1.5%Mg-2%Cu-0.5%Mn-0.25%CrESD

Extra Super Duralumin

58 60 kg/mm2 570 590 MPa48 52 kg/mm2 470 510 MPa10 1630 kg12533 km/h432km/h100km/h19421943 7075 Al-5.7%Zn-2.5%Mg-1.6%Cu-0.25%Cr

2.4

13

ESD

Fig. 4 Patent of Extra Super Duralumin, No. 135036 2)


14

Fig. 515

3.1Al-Zn-Mg

GHQ

Al-Zn-MgAl-Mg-SiAl-Zn-MgHD

Al-5.4%Zn-2.0%Mg-0.55%Mn-0.25%Cr

Fig. 6Al-Zn-Mg1617PFZ8Fig. 771507475Fig. 5 Sayings of Dr. Igarashi collected by Dr. Nagata 15).

1.

2.

3.

4.

5.

(1) At first, it is necessary to master company s history, persons, technology and so on entirely. It takes 4-5 years to master them. Learning lectures in a school only is insufficient.

(2) Industries develop by the daily progress of theory and experiment. It is troublesome to regard the immature theory as absolute.

(3) Fact is important! Don t talk various quibbles. Progres-sion and development are generated only when a new fact inconsistent with expected results is found.

(4) When questions arise, it is necessary to consider repeatedly why they occur and investigate them thor-oughly.

(5) Theme is important. But it is problem who decides the theme.

Fig. 6Dr. Yoshio Baba1935-2012


PFZ18

606160637003Aluminum Association

19Al-Mg-Si217

3.2Al-Zn-Mg-Cu

1980B7671980 19832019811821722

B7677075Fig. 8

Fig. 8 B767s fuselage constructed with frames, skins and taper-rolled stringers (left). Manufacturing process of a taper-rolled stringer for airplanes (right) 17) .

Fig. 7Precipitation around Zr (7150) or Cr (7475) compounds in these alloys air-cooled (1 K/s) from solution heat treatment and aged at 163 -44 h 18).

0.2 m

0.2 m

(a) 7150 (Zr)

(b) 7475 (Cr)


177075197950 m17B767B7779172324KYB2625

1983 1986261986 1989Al-Li

27Fig. 97475Al-Li10-3s-128

4.17475

4.1.1

1970292

707510 m Rockwell InternationalWert3031Fig. 10400 -8 h0.75 1 m22090%482Wert3270757475360 480

Fig. 9Door panel model formed superplastically using a 7475 alloy sheet with fine grains compared with a conventional structure. SPF structure consists of 3 SPF parts and 80 rivets, while conventional one consists of 45 pressed parts and 400 rivets. Cost saving of 30% and weight saving of 15% were achieved by SPF 26) . This panel was superplastically formed by Mitsubishi Heavy Industries.

Conventionaldesign

New design: Integrated door model with SPF beam and stiffener

Conventional structure(45 Parts, 400 Rivets)

SPF structure(3 Parts, 80 Rivets)

Cost saving 30%Weight reduction 15%


90480 -5 minFig. 11Table 132Wert400 -8 16 h420 -16 h4004 h

42011 m

4.1.2

400 -8 h480 -2 h4Fig. 12Fig. 1332480 -2 h0.5 2 m0.1 0.2 mE-phaseAl18M3Cr2480Fig. 14Fig. 15

Grain size in L-LT plane/m

Solution heat treatment

Precipitation treatment

Holding time/hWater quenching Furnace cooling

Temperature / 1 2 4 8 16 1 2 4 8 16

480-5 min WQ

360 11 9.5 9.5 19 19 16380 8 8 8 16 16 13400 8 8 6.5 6.5 13 11 11 11420 9.5 9.5 8 6.5 11 11 11 11440 9.5 9.5 9.5 11 11 11 11 11460 11 11 11 11 480 15 15 11 11

No SHT 290 8 11 380 15 11 Process: Solution heat treatment (480-5 min WQ)Precipitation treatment (360-480/1-16 h WQ, FC) Cold rolling (90%)Solution

heat treatment (480-5 min) WQ

Table 1 Effect of precipitation treatment on the grain size in L-LT plane of recrystallized sheet 32).

Fig. 11 Grain refinement process for investigating the effect of conditions of precipitation treatment and cooling rate on recrystallized grain sizeWQWater Quenching, FC: Furnace Cooling (25 /h) 32).

WQ FC

Precipitation CR SHT500

400

300

200

100RT

Tem

pera

ture

/

Fig. 10 Grain refinement process developed by Rockwell International for superplastic 7075 alloy sheets

Reprinted with permission of TMS 30), 31).

Solution treatment

Overaging

Rolling

Recrystallization

Tem

pera

ture

/

Time

482-3 h

400-8 h

482-30 min

22090%

(510 pass)

482

400

200

20


Fig. 16

32480Fig. 14

Fig. 12 Effect of precipitation treatment on the microstructures of the cross section before and after cold rolling ( all pictures are in the same magnification).

Before cold rolling After cold rolling

400

-8 h

WQ

400

-8 h

FC

480

-2 h

WQ

480

-2 h

FC

50 m50 m

Fig. 13 Effect of precipitation treatment on the TEM structures before and after cold rolling.

Before cold rolling After cold rolling40

0-8

h W

Q40

0-8

h F

C48

0-2

h W

Q48

0-2

h F

C2 m2 m

2 m2 m

2 m2 m

2 m2 m

4 m4 m

2 m2 m

4 m4 m

4 m4 m

Fig. 14 Effect of the resolved solute atom content on TEM structures of cold rolled sheet, tangled dislocation structures in WQ and dislocation cell structures and subgrains by dynamic recovery in FC are observed.

400-8 h WQ 400-8 h FC

0.5 m0.5 m0.5 m0.5 m

Fig. 15 Ring-like tangled dislocation structures around E-phase containing chromium.

0.2 m0.2 m

E-phase E-phase

E-phase


400 -8 hFig. 17320340

3235033400Fig. 184801010

480Fig. 1934

400 -8 h

Fig. 17 TEM structures heat-treated at several conditions in a salt bath using the sheet treated by precipitation at 400 -8 h WQ followed by 90% cold rolling.

320-300 s 340-90 s

320-1200 s 400-30 s

2 m2 m

4 m4 m

2 m2 m

2 m2 m

Fig. 16 Effect of precipitation treatment on the change of electrical conductivity before and after cold rolling of 50% 32).

Precipitation

Furnace cooling

Water quenching

Solid Solution

Before cold rollingAfter cold rolling(Reduction 50%)

360400440480

Aging time/h

Elec

tric

al c

ondu

ctiv

ity/I

ACS

%50

40

30

201 2 4 8 16


480Fig. 20

400 -8 hFig. 2132355N5N

4.1.3

36480 -2 h480 -5 min

Fig. 19 C-curve of precipitation in 7075 alloy (Schematic) 33).

350

Time

Tem

pera

ture

Al3FeAl18Mg3Cr2 (E-phase)

MgZn2, (AIZnMgCu)Al2CuAl2CuMg

500

350

Fig. 20 TEM structures at micro bands and microstructures at shear bands during recovery and recrystallization of the sheet (480 -2 h WQ, 90% CR) heated at 340 360 in a salt bath 32).

340-5 min

L-LT plane 360-90 s L-ST plane

340-20 min 360-5 min

4 m4 m

Fig. 18 TEM structures heat-treated at 480 in a salt bath using the sheet treated by precipitation at 400 -8 h WQ followed by 90% cold rolling.

480-1 s 480-10 s

2 m2 m2 m2 m


8.6 m37Fig. 2232 h38420480 -32 h

500

Fig. 23747510-4 s-110-3 s-138

4.2 7475

7475

Fig. 21 Schematic model of the grain refinement process in a 7475 alloy sheet 32).

E-phase

E-phaseMicroband

Soluteatoms(Mg, Zn, Cu)

Largeparticles

E-phase

Intermediateheat treatment

As coldrolled

Low temp.

During heating

Cr, FeCr, Fe

Cr, Fe

Cr, Fe

finegrain

High temp.

Mg3 (Al, Cu, Zu) 5-phase

Zn

MgMg

MgCu

Cu

Cu

Cr, Fe

Cr, FeZn

Zn

Fig. 22 Effect of preheating temperatures for 32 h in a salt bath on cavitations during superplastic deformation at 500 and 2.5x10-4 s-1 without holding at 500 before tensile test in a 7475 alloy SPF sheet 38).

Are

al fr

actio

n of

cav

ity/%

True strain

14

12

10

8

6

4

2

00 0.5 1.0

Original sheet400420440460480500520

Pre-heating time : 32 h (in salt bath)Pre-heating temperature

T=500(Temperature of tension test)=2.510-4 s-1 Holding time : 0 s

400

520440500460

1.5480

420

Original

Fig. 23 Effect of heating rate (salt bath or air furnace) and holding time in pre-heating at 480 and tensile test speed at 500 on the elongation at 500 38).

1000

800

600

400

200

0

Pre-heating time/h/at 480 32

Elom

gatio

n/%

5.610-4 s-1

5.610-3 s-1 (Air Furnace)

5.610-3 s-1 (Salt Bath)


10-4 s-113910-3 s-1

20 800.6 mmFig. 2440655002.710-3 s-1

Fig. 25Fig. 265040480100 m10 m

50500Fig. 27402.710-3 s-1800 900

Fig. 26 Relation between optimum range of pre-strain temperature and recrystallization peaks in DSC curve 40).

600

Tem

pera

ture

/

Reduction of cold rolling/%

Recrystallization(Peak in DSC curve)

Optimum range ofpre-strain forming

500

400

300

200 20 50 80

Fig. 25 Effect of cold rolling reduction and pre-strain temperature on elongation at 500 40).

300 340 380 420

Temperature of pre-strain forming/

1000

800

600

400

200

0

480-2 h WQ CR (20, 50, 80%)

20%

50%

CR=80%

Pre-strain

SPF

5.610-3s-165% T5002.710-3s-1

Elon

gatio

n/%

Fig. 24 Process and its conditions of thermomechanical treatment for two-step deformation, that is, pre-strain at low temperature and tensile test at high temperature 40).

400

480500

400

300

200

100

RT

IA1 IA2 Pre-strain

FC WQ WQ FC

CR CR

20%50%80%

t3.0t1.2t0.75

t6

RecrystallizationTMT for SPF sheet Tension test

Tem

pera

ture

/


10-3 s-1

4.3

7075Fig. 28MILO410 4502 h400 2 h20%300 -2 h400 -2 h480 -5 min400 -2 h

41400 -2 h300 -2 hOO

198042198143

198344198645

Fig. 28 Effect of precipitation treatment conditions and cold rolling reduction on the grain size of 7475 alloy sheet heated at 480 in a salt bath

Process: hot rolling cold rolling (50%) recrystallization (480 -5 min WQ, salt bath) precipitation treatment (none, 300 -2 h WQ and FC , 400 -2 h WQ and FC) cold rolling (0-90%) recrystallization (480 -5 min WQ, salt bath) measurement of grain size.

Grai

n si

ze/

m

0

2040

60

80

100120

140

160

0 20 40 60 80 100

Reduction of cold rolling /%

300C-2 h WQ300C-2 h FC400C-2 h WQ400C-2 h FC480-5 min WQ

Fig. 27 Effect of intermediate heat treatment (IA2 in Fig. 26) on high temperature elongation at 500 40).

Intermediate heat treatment

Elon

gatio

n/%

IACR50% Pre-strain SPFPre-strain=360Tp

=340Tp=T

T

Tp

=290Tp

=290Tp

1000

800

600

400

200

0400WQ

5.610-3 s-165%

SPF =5002.710-3 s-1

400FC

480WQ

480FC


87475705019 21Al-Li

Wert3031

WertBimodal 30317000

1000464748355N

Al-Li7000700060003000Al-Fe


100080007000

UACJUACJFurukawa-Sky-ReviewUACJ

Technical Reports

774 TP3 TP3 Timely Professional5Production Process and Price CostPatent or TP310 20

1 53201260-78. 2 542013264-326. 3

1986. 4

1995 5

1989 6 1001991171. 7 M.B.W. Graham and B.H. Pruitt R&D for Industry, A

Century of Technical Innovation at Alcoa, Cambridge, 1990, 170.

8 20No. 1911950, 2.

9 3819958.


10 199559.

11 642014,111-116.12 1970

64. 13 29198893-9814 1120043815 602010192-20116 Y. Baba: Tran. JIM.71966224.,

9196824-31.17 502000398-408.18 341984689-

701.19 18197768-79 .20

No. 5061981No. 6031982No. 7021983

21 No. 131985

22 46199689.

23 No. 8071994No. 9041995

24 491999161-165.25

652015, 95-100.26

No. 8021984No. 9011985No. 60011986

27 Al-LiNo. 1051987No. 2051988No. 3071989

28 391989817-823.29 36199537-46.30 J.A. Wert, N.E. Paton, C.H. Hamilton and M.W. Mahoney:

Metallurgical Transactions A, 12A1981, 1267-1276.31 J.A. Wert: Superplastic Forming of Structural Alloys,

edited by N.E. Paton and C.H. Hamilton, TMS-AIME, 1982, 69-83.

32 411991331-337.33 391989, 587-606.34 C.C. Bampton, J.A. Wert and M.W. Mahoney: Metallurgical

Transactions A, 13A1982, 193-198.35 642014285-291.36 1387695

58198312837 411991338-343.38 411991446-452.39 291988

58-68.40 411991453-458.41 1985.42 211980

123-139.43 311981195-205.44 221983115-

120.45 271986333-338.46 391989, 184-189.47 642014179.

48 642014279-284.

Hideo YoshidaUACJ

Documents

超々ジュラルミン開発の伝統を受け継いで ― 超塑 … Technical Reports，Vol.2 （2015） 43 超々ジュラルミン開発ので 超塑性材の研究開発と

超々ジュラルミン開発の伝統を受け継いで ― 超塑 … Technical Reports，Vol.2 （2015） 43 超々ジュラルミン開発ので超塑性材の研究開発と