MATERIALS

METALS

FASTENEPS

NONMETALS

PROTEcT ; /E TREATMEMT

OCT 9 1987 IGS C51-99-014-Q1

PR1NT DATE OCT 1988 l

ALUMINUM ALLOY APPLICATION -"707/727/737/747 AIRPLANES

General

Approximately 80 percent of the basic airframe structure is aluminum. Aluminumalloys are easily machined and fabricated compared to the steel and titanium al-loys. Aluminum alloys used for aircraft generally require corrosión protectionsystems including: (a) anodizing or chemical conversión coatings for a corro-sión resistant surface; and (b) the use of corrosión inhibiting primers andenamels.

s

The alloys of aluminum use a variety.of alloying elements and heat treatmerits toachieve an optimum combination of toughness, strength, fatigue, and corrosiónproperties for each portion of aircraft structure. The thermal and mechanicaltreatments are identified by a temper designation (TXXX) which is a suffix tothe alloy designation, e.g. 2024-T351 píate. The specific alloy systems used byBoeing are discussed below:

C51-84-532-01B 3826CSec B 4 MAR 01 1983

7075-T73 FORGINGSBODY ANO WINGS

•BULKHEAOS

• FITTINGS

VERTICAL TAIL(7075-T6)• SKINS

STRINGERS

SKIN (2024-T3)STRINGERS (7075-T6)

LOWER SKINS (2024-T3)• STRINGERS

• SPAR CHOROS(2024-T3)

HORIZONTAL TAIL• LOWER SURFACE

(7075-T6)

• UPPER SURFACE(2024-T3) (PARTIAL)

UPPER SKINS (7178/7075-T6)• STRINGERS• SPAR CHOROS

KEEL BEAM CHOROS (7075-TG & T73)

JUN 08 1987

Sec D

ALUMINUM ALLO Y/APPLICATIONS707/727/737/747 AIRPLANES

C51-84-032-01C

ALUMINUM ALLOY USAGE

1. 2024

2024 is a copper-magnesium aluminum alloy that is generally used in the naturallyaged (room temperatura aged) condition of the T3 or T4 tempers. This alloy has thebest fatigue strength and fracture toughness of the structural alloys and is conse-quently used for tensión applications such as lower wing surface and upper surfaceof the horizontal stabilizer. The body skins are also 2024 to provide máximumtoughness. Body skins are ciad to provide corrosión resistance in áreas left un-painted.

2. 7075

7075 is a copper, magnesium, zinc aluminum alloy that is often used in the -T6 orpeak aged condition for structure requiring high compression and shear strengthssuch as upper wing surface, lower surface of horizontal stabilizer, vertical stabi-lizer, and body frames and stringers. The same alloy is usud in the overaged or-T73 condition for fittings machined from forgings, píate and extrusions. The T73temper offers excellent stress corrosión and exfoliation corrosión resistance.

7178

7178peak

is a high strength copper,aged condition for

magnesium, zinc aluminum alloy that is used in theits high compressive strength. Application has been pri-

marily for upper wing surface and keel beam chord. It is no longer used for designbecause of its susceptib i 1 ity to exfoliation corrosión. Substitution of 7075-T6for 7178 requires a 15 percent increase in thickness und/or área.

356/A356/A357 Aluminum Casting

Aluminum castings are used throughout the airplane for hydraulic manifolds and con-trol linkages and are a lower cost ineans of producing complex shapes or parts.

C51-84-533-01CSec 13

9034ÍJUN 08 1987

ALUMINUM ALLOY USAGE ON BOEING AIRPLANES

ALLOYSPRODUCTFORMS

MAJORAPPLICATIONS USAGE RATIONALE

2024-T3

7178/7075-T6

2024-T3

PLATE / EXTRUSIÓN

PLATE/ EXTRUSIÓN

SHEET

7075-T6

7178/7075-T6

7075-T73

356/A356/A357

PLATE/EXTRUSIÓN

EXTRUSIÓN

FORGING/EXTRUSION

CASTING

LOWER WING SURFACEUPPER HORIZONTAL TAILSURFACE

UPPER WING SURFACELOWER HORIZONTAL TAILSURFACE

BODY

VERTICAL TAIL

KEEL BEAM CHORO

WING ANO BODYBULKHEAOS ANDFITTINGS

HYDRAULIC MANIFOLDSAND CONTROL LINKAGES

HIGH FATIGUE AND FRACTUREPROPERTIES WITH ADECÚATETENSILE STRENGTH ANDCORROSIÓN PROPERTIES

HIGH COMPRESSION YIELDWITH ADEQUATÉ FATIGUE,FRACTURE, AND CORROSIÓNPROPERTIES

HIGH FATIGUE AND FRACTUREPROPERTIES WITH ADEQUATÉSTRENGTH (TENSILE,COMPRESSION AND SHEAR) ANDCORROSIÓN PROPERTIES

HIGH STRENGTH (TENSILE,COMPRESSION, ANO SHEAR)WITH ADEQUATÉ FATIGUEFRACTURE AND CORROSIÓNPROPERTIES

HIGH COMPRESSION STRENGTHWITH ADEQUATÉ FATIGUE,CORROSIÓN AND FRACTUREPROPERTIES

EXCELLENT RESISTANCE TOSTRESS AND EXFOLIATIONCORROSIÓN AND ADEQUATÉSTRENGTH, FATIGUE ANDFRACTURE PROPERTIES

LOWER COST THAN FORGINGS,WITH ADEQUATÉ PROPERTIES

MAR 1 1983Sec B

ALUMINUM ALLOY USAGE

C51-84-033-01A

ALUMINUM ALLOY APPLICATIONS - 737-300/757/767 AIRPLANES

General

The 757/767 and the new 737-300 airplanes use improved alurainura alloys for wingstructure and forged fittings. These alloys are based upon earlier alurainura alloysand use similar but refined chemistries in addition to special processing controls(such as therraomechanical treatraents, etc.) to improve properties. The alloys usedon the 707/727/737/747 are still used in the body and other áreas as described inthe earlier section. The five new improved alloys are as illustrated.

These improved alloys often will not be available for use in repair applications.The 2024T3/T4 and 7075-T6 alloys may be used as substitutos by increasing the áreasand/or thickness by 15 percent./

C51-84-534-01CSec B

9034ÍJUN 08 1987

7075-T73, 7050-T7367175-T736 FORGINGS

BODY ANO WINGS• BULKHEADS• FITTINGS

LOWER SKINS (2324-T39 PL)• STRINGERS• SPAR CHOROS

(2224-T3511 EXTR.

VERTICAL TAIL7075-T6• SKINS• STRINGERS

HORIZONTAL TAIL7075-T6• SKINS (LOWER)• STRINGERS

2024-T3 (PARTIALUPPER SKINS)

tIPPER SKINS (7150-T651 PL.)STRINGERS(7150-T65I1 EXTR)

KEEL BEAM CHOROS (7150-T6)

JUN 8 1987Sec B

ALUMINUM ALLOY APPLICATIONS737-300/757/767 AIRPLANES

C51-84-034-01C

A I . U M I N U M A L L O Y USAGli 757 /767

1. 2224 1-xtrusion

This alloy has higher tensile strength, fatigue and fracture properties than thebaseline 2024 extrusions with equivalent corrosión resistance. The materialstrength and toughness is achieved by tighter control of chemical compositionand application of special process controls during fubrication.

2. 2324 Píate

This alloy has higher tensile strength and fatigue properties than the baseline2024 alloy with equivalent fracture and corrosión resistance. The materialstrength is achieved by thermomechanical processing, i.e., cold work and pre-cipitation hardening.

3. 7150 Píate and Extrusión

This alloy has higher compressive strength than baseline 7075 alloy with equiva-lent or better fracture properties and corrosión resistance. The materialstrength is achieved by tighter control of chemical composition and applicationof special process controls during fabrication.

-1. 7050 Forging

This alloy is used primarily for thick section forgings greater than 3.0 incheswhere additional strength may be utilized. The alloy has equivalent fatigue andfracture properties to the baseline 7075-T73 when used as 7050-T736.

5. 7175 Forging

This alloy is used primarily for forgings less than 3.0 inches where additionalstrength may be utilized. The alloy has equivalent fatigue and fracture proper-ties to baseline 707S-T73 when used as 7175-T736.

C51-84-535-01Ü 3474CSec b 10 MAR 01 1983

ALLOYSPRODUCTFORMS

MAJORAPPLICATIONS USAGE RATIONALE

2324-T392224-T351

7150-TG

2024-T3

7D75-T6

7075-T6

7150-T6

7075-T73,

7050/7175-T736

3G5/A356/A357

PLATEEXTRUSIÓN

PLATE/EXTRUSIÓN

SHEET -

PLATE/EXTRUSIÓN

PLATE/EXTRUSIÓN

EXTRUSIÓN

FORGING

FORGING

CASTING

LOWER WING SURFACE

UPPER WING SURFACE(

BQDY

HORIZONTAL TAIL

VERTICAL TAIL

KEEL OEAM CHORO

WING AND BQDYFITTINGS

WING ANÜ BODYBULKHEADS ANO FITTINGS

HYDRAULIC MANIFOLD ANDCONTROL LINKAGE

HIGHER TENSILE STRENGTHTHAN 2024-T3 WITH ADEQUATEFRACTURE, FATIGUE ANOCORROSIÓN PROPERTIESHIGHER STRENGTH THAN 7178/7075-T6 WITH AOEQUATE FATIGUE,FRACTURE AND CORROSIÓNPROPERTIES

NO CHANCE - SAME RATIONALEAS FOR QTHER AIRPLANES

HIGH STHENGTH WITH ADEOUATEFATIGUE, FRACTURE, ANOCORROSIÓN PROPERTIES(SIMILAR TO OTHEHAIRPLANESÍ

NO CHANCE - SAME RATIONALEAS FOR QTHER AIRPLANES

HIGHER COMPRESSION STRENGTHTHAN 717B/7075-T6, WtTHAOEOUATE FATIGUE ANOCORROSIÓN PROPERTIES

NO CHANCE - SAME RATIONALEAS FOR OTHER AIRPLANES

HIGHER STRENGTH THAN 7075-WITH EQUIVALENT FATIGUE ANDFRACTURE PROPERTIES

NO CHANCE - SAME RATIONALEAS FOR OTHER AIRPLANES

MAR 1 1983

Si-c: D

ALUMINUM ALLQY USAGE 757/767C51-84-035-01A

11

ALUMINUM ALLOY IIEAT TREATMENT

The primary operations or processes in the heat treatment of an aluminum alloyare solution heat treatment and age hardening. ,

Solution treatment consists of heating the aluminum part to 800 to 900 degreesF. (depending on the alloy) and quenching the part in cold water. Occasionallyparts are quenched in hot water to reduce the resultant part distortion orwarp. Hot water quenching should not be allowed with 2024 alloys since the re-duced cooling rate lowers the resistance of 2024 material to exfoliation corro-sión.

The part is then aged to increase its str.ength. Sotne alloys will naturally ageat room tempera ture. Other alloys and tempers mus't be artificially aged in anoven. The artificial aging tempera tures vary from 250 to 350 degrees F. depend-ing on the alloy and temper condition desired.

An abbreviated chart of the aluminum temper designation system is shown.

The only heat treat designations that Boeing or the airlines can accomplish arethe -T42, -T62 or the -T73 conditions.

C51-84-543-01 9034ÍSec B 12 MAY 02 1984

-T6

STANDARD HEAT TREATEDDESIGNATION.

TEMPER DESIGNATION

-T3: SOLUTION HEAT TREATED. COLÓ WORKED ANDNATURALLY AGED.

-T4: SOLUTION HEAT TREATED AND NATURALLY AGED.

-T42: SOLUTION HEAT TREATED AND NATURALLY AGEDBY THE USER. APPLIES TO 2024-0 AND 6061-0.

-T6: SOLUTION HEAT TREATED AND THEN ARTIFICIALLYAGED. NOT APPRECIABLY AFFECTED BY COLÓ WORK:FOR MOST MATERIALS THE -W AND -T4 TEMPERSARTIFICIALLY AGE TO -T6.

-T62: SOLUTION HEAT TREATED AND THEN ARTIFICIALLYAGED BY USER. APPLIES TO A NUMBER OF ALLOYS (E.G.2024. 6061. 7075), WHICH HAVE BEEN HEAT TREATEO ANDAGED BY USER.

INDICATES MINOR STRAIGHTENINGUSE TO MEET STRAIGHTNESS ANDFLATNESS TOLERANCES. THIS DIGITIS OIF NO STRAIGHTENING ISALLOWED.

MATERIAL WAS STRETCHED TOACCOMPLISH STRESS RELIEF. THEOIGIT 2 WOULD BE USED HEREWHEN COMPRESSIVE METHODS AREUSED.

INDICATES MATERIAL HAS BEENSTRESS RELIEVED.

-T73: SOLUTION HEAT TREATED AND OVERAGED.THIS TEMPER APPLIES TO SEVERAL 7000 SERIES ALLOYSAND INDICATES A GREATER DEGREE OF OVERAGING RE-QUIRED FOR HIGHER STRESS CORROSIÓN RESISTANCE.MATERIAL IN THIS TEMPER IS ALSO IMMUNE TO EXFOLI-ATION CORROSIÓN. AS APPLIED TO 7075 OR 7175. THE-T73 TEMPER IS VIRTUALLY IMMUNE TO STRESS-CORROSION.

SEP 29 1987Seo B

ALUMINUM ALLOY HEAT TREATMENT

C51-84-061-01A

13

ALUMINUM WELDING

Welding

Welding of 2000 and 7000 series aluminum alloys is not permicted. The weldingprocess changes the structure of the metal and produces a permanent loss-of properties for these alloys. Other alloys such as 6061 are weldable and may be weldedper the Repair Manual. See the appropriate Boeing documents for specific restric-tions and áreas approved for welding.

C51-84-536-01E 9034ÍSec B 20 JUN 08 1987

WELDING

fulIon -

Utld rtpilrltif o' Ptrtt ind

I) UK 11 H.i) Renoit d(((Ct b/ qrmdl

irod i f I f d.]J Wtld recilr «hen u H

Conildcr huí un

WU01IJGc-í nttill ptr BU

ordfr o' prt'trenct:

r i l lng» drlllliq. tic,. *nd trien uir it

{ondidon oí Piri.«nd multint propfrftt l m trie r . j í i f í c t t r : roñe.

lptctlon M rcnulrttl J Í . ÍT- i^, T- . - -:: U«ri> «ccampl i ir>ed.

-f - A -* U rvp4lr M fltcriljry, .-j- ' . . ' ¡ . . ..'..-! 11 (he • -— . - r lniInj<Honu

U Prcclfinin^ prccen.? ) T I O L . - I S ] prflf tu ,1' Fll l tr «cltl (üfld rod :.',:;4) D«1niptct1oi ftquirrMentt.5) A ilflt«B«nt iptci'ring timt^ t rt-*en

1113 tic rvtglUnl rvduc e4 -v. ' c - • i . irocijont -••.-'- rué pirt li.jn * h«t trri^td

, procedurtí mil t4

in ' . • = tett ji.jn orlar la

CAUIION: Pri '%1'. tlruClurtl pin« -.-.IU . nol M -flJDotlfig J^prnvjl.

TI - tA l -4* . «rauin'i]tfld C4K Pírll 'ii-;ov-íí«-i>i _ :_Camrcul \i purtIIURHa,• . - JA ' -: ;: lubm

rfgurM -ItlKlul

L¿_J Furn.ct itnn nli*r rciuiríd lor clllt '»• -*ldi. HMKIIinti (orclin 'B' -fluí.

NO!E: Ir» -tliWnt ifull t» p)ittd in ih« ilnii nlltf (urnict mcfl ihitIhe Htld riott no< coa I bílan t'1* ^>ninj» prvhcit tarveriturt un I i I

í ) > Í5ÍI-IÍ 11 luDJicl U c r j ; i i n ) »ntn .tldti. Uit .fl or -14 Icrotrl.S o i t L l o n nui ind iqe :o -Ti candillaii ir'ítr Hcldlng ur ilnplí <gt tathe -T6 ifttr wrltflng if luiinB joinl itrtngth ll ~'0i requinte.

I ti sni i j .-oí M »t*t itf í iba» Ui» 160 - ZOO «i Irtij*.

JUN 08 1987Scc B

ALUMINUM WELDING

CS1-B4-036-01C

21

TITANIMUM ALLOY APPLICATIONS

Titanium (Ti) alloys are used in a variety of structural and non-structuralapplications in Boeing airplanes. Titanium alloys are used generally for one ormore o£ the following reasons:

excellent corrosión resistanceweight-savingselevated temperature stabilityto alleviate volume constraint problemscompatibi1 ity with other materials

Titanium alloys are ver y corrosión resistant and do not p i t from cor'rosionprocesses. Titanium alloys are approximately 40% less dense than steel so thatweight savings are often realized by using titanium alloys ruthe,r than steels.They are used in place of aluminum alloys when:

(1) elevated temperature stability is required;(2) an aluminum alloy component would be too largo to intégrate into the

overall structure and a titanium alloy component would fit; and/or,(3J aluminum alloy is not desired to be in direct contact with another

material for galvanic corrosión reasons.

C51-84-537-01A 3489CSec B 22 MAR 01 1983

APU FIREWALL

MAIN LANDING GEAR BEAMSAND ASSOCIATED STRUCTURE

WINDOW SILLAND POSTS

OUTBOARD FLAPSUPPORT LINK

INBOARD FLAPSUPPORTLINK

ELEVATORACTUATORFITTINGS

INBOARD AUXILARYSLAT TRACKS

- MLG ACTUATOR SUPPORT FITTINGS- FORWARD LANDING GEAR TRUNNION

BEARING HOUSING '

MAY 19 1983Sec B

THRUST REVERSER FITTINGS

HYDRAULIC LINESSPRINGSFITTINGS (STRUCTURAL ANO NON-STRUCTURAL)PNEUMATIC DUCTSFASTENERS

fTITANIUM ALLOY APPLICATIONS!

C51-84-037-01B

23

TITANIUM ALLOY USAGU

There are a variety of titanium alloys chosen for specific applications basedupon needed material properties and a balance between «atería!/fabricación costsand component weight. The follouing are the primary alloys used by Boeing, thetypes of applications, and the reasons for selection.

Commercially Puré (CP) Ti - is the lowest strength titanium grade used byBoeing. CP Ti is used for applications such as scuff plates and pneumaticducts. CP Ti is also employed for many fittings and clips in áreas of highercorrosión potential such as near galleys and lavatories.

TÍ-3A1-2.5V - is used on the 757/767 for high pressure hydraulic tubing toreduce weight oyer tlie previously used stainless steel tubing.

TÍ-6A1-4V - is the most cxtensively used alloy. There are three heat treat-ments used depending upon tlie specific requi rement for component. Applica-tions for this alloy include:

(1) Windshield'frame for 757/767; 767 floor support structure;(2) landing gear beam for the 747 $ 757; and(3) 767 APU firewell; a variety of structural fittings, fasteners and

hydraulic fittings.

Ti-6A1-6V-2Sn - is higher strength than TÍ-6A1-4V which allous more weightsavings. Ti-6A1-6V-2Sn is used primarily on fittings on the 747 landing gearand wing área as well as extensive use in the flap support structure on the747SP.

C51-84-538-01A Sht 1 3492CSec B 25 MAR 01 1983

TITANIUM ALLOY USAGE

Ti-10V-2Fe-3Al - is a newer titanium alloy with higher strength than eitherTi-6Al-6V-2Sn or TÍ-6A1-4V. This newer alloy is used in forgings in the 757Trunnion Dearing Housing, Auxiliary Slat Tracks, and Door Hinges and will beused in the 737-300 in the Overwing Nacelle Fitting. Ti-10V-2Fe-3Al, because ofits higher strength, offers more weight savings. Because Ti-10V-2Fe-3Alexhibits improved low temperature forging characteristics over TÍ-6A1-4V it isan attractive material for near nct shape precisión forgings.

Ti-13V-1lCr-3Al is used in the 747, 757, and 767 airplane in spring applica-tions. This alloy is used as a spring material because its low modulus o£elasticity and reduced density allows up to 70*. weight savings over steel.

C51-84-538-01B Sht 2 3500CSec B 26 MAR 01 1983

TITANIUM ALLOYS USEO ON BOEING AIRPLANES

ALLOY

COMMERCIALLYPURÉ TI

TI 3AL-2.5V

TI-6AL-4V

TI-6AL-6V-2SN

TI-10V-2FE-3AL

TI - I3V-1 ICR-3AL

HEAT TREATCONOITION

ANNEALEO

COLD-WORKEO ANOSTRESS RELIEVED.ANNEALEO

ANNEALEOBETA ANNEALEOSOLUTIONTREATEOAND AGEO

SOLUTIONTREATED ANDAGED

SOLUTIONTREATEO ANDAGED

SOLUTIONTREATED ANDAGED

STRENGTHRANGE. KSI

50-80

100-125

120 160

150 170

180

200-230

• FORMS

SHEET. STRIPPLATE

TUBING

SHEET, PLATE.FORGINGS, EXTRU-SIONS, CASTIÍIGS

PLATE ANDFORGINGS

FORGINGS

SPRINGS

APPLICATIONS

SCUFF.PLATES. DOORTHRESHOLOS. PNEUMATIC OUCTS.FIREWALLS. MISC. NON STRUC-TURAL FITTINGS.

HIGH PRESSURE HYORAULICTUBING ON 757. 767

LANOING GEAR ÁREA.FIREWALLS. NO. i WINOSHIELDFRAMES ON 757 AND 767. FLAPFITTINGS. 767 FLOOH SUPPORTSTHUCTURE. MISC. STRUCTURALFITTINGS. HYORAULIC FITTINGS,FASTENERS

USED PRIMARILY ON747. FITTINGS INLANOING GEAR ANOWING ÁREA. USEOEXTENSIVELY ON FLAPSUPPORT STHUCTUREOF 747 SP

757 TRUNNION BEARING HOUSINGAUXILIARY SLAT TRACKS DOORHINGE MECHANISM737-300 OVERWING NACELLEFITTING

747. 757. 767 SPRINGS INLANOING GEAR ANO DOOR ÁREAS

USAGE RATIONALE

BETTEH STRENGTH TO WEIGHTRATIO THAN STAINLESS; EXCELLENT CORROSIÓN RESISTANCE;FORMABLE

WEIGHT SAVINGOVER STEEL

WEIGHT SAVING OVERSTEEL: VOLUME CONSTRAINTSOF Al.

HIGHER STRENGTH THANTI 6AL-4V THEREFORE GREATERWEIGHT SAVING

WEIGHT SAVING

WEIGHT SAVINGOVER STEEL

^MY 19 1983Sec D

TITANIUM ALLOY USAGEC5184038-01B

27

UNIQUE IIANDLING CIIARACTL-RI STICS OF TITANIUM ALLOYS

1 . Genera 1

2. Stress Relieve after Cold-forming or Straightening

Straining of titanium alloys can cause a signifigant drop in the yield strengthdue to a me tal lurgical phenomenon and introduces high residual stresses. Stressrelieving removes these effects and restores the original properties. Stressrelief is not required for the CP alloys.

3. Weld in Protective Atmosphere or with Shielding Gases

Without inert gas p r o t e c t i v c shielding during wulding, t i tan ium alloys can pick-up oxygen or hydrogen. Meat-treated alloys must be reheat created after weld-ing. See SIIM for requi remen ts .

4. Assure Protective Coating Integrity on Potential Skydrol Exposure Áreas

In áreas where skyclrol exposure at eleva ted te m p e r atures can, occur, a protectivecoating is used to prevent the skydrol from contacting the titanium alloy. Theprotective coatings must be continuous to be effective.

5. Use Caution Wlien G r i n d i n g Titanium Materials

Grinding as a final f i n i s h operación must be done with care. The grindingoperation can produce both: (a) high tensile stresses at the surface whichaids early crack i n i t i a t i o n , and (b) surface damage in the form of small tearsunless adequate precautions are taken. Overhaul Manual Section 20 describes theacceptable methods to be used for metal removal.

CS1-84-539-01B 9034?Sec U 28 JUN : 1987

WELDING - NO

GRINDING - WITH CARE

REQUIRES INERT GAS PROTECTIVE SHIELDING

JUN 08 1987Sec B

UNIÜUE IIAIMDLING CHARACTERISTICS OF TITANIUM ALLOYSC51-84-039-01D

29

STEEL APPLICATIONS

Approximately 12-16 percent of the basic airplane structure is alloy steel andstainless steel. The high strength and high modulus of elasticity are theprimary advantages of the high strength steels. The high strength and modulusare useful for designs with space limitations such as with some landing gearcomponents.

Alloy selection considera tions include service temperature, strength, stiffnessfatigue properties and fabricabi1 ity.

C51-B4-540-01A 3518CSec B 30 MAR 01 1983

INBOAHD FLAP TRACKS.4340M

FLAP LINKAGE.15-5PH ANO4330M

REAR ENGINE MOUNT,9 NI-4CO-.30C

HYDRAULIC LINES

LANDING GEAR4340M

FRONT ENGINE MOUNT, STRUT LOWERSPARS. WEB, AND CHOROS,15-5PH

ENGINE MIDSPARATTACH FITTINGS,4330M

•SLAT TRACKS.4340M

OCT 24 1983Soc D

STEEL APPLICATIONS

C51-84-040-01A

31

STEEL ALLOYS AND TEMPERS

Material Designations

given to most low alloy steels are based upon an AISI (AmericanInstituto) system that refers to the chemical composition of the

alloy. The first two digits refer to the specific primary alloying elements,the last two (and the last three digits in a five digit number)percentage of carbón contained in the alloy.

DesignationsIron 5 Steel

refer to the

10XX -41XX -43XX -52100 -93XX -

r examp]

refers to plrefers to chrefers to nirefers to arefers to af eren t ra t i oloys) .

Le; 4340 refersperccnt carbón.

plain carbón steels (contain only carbón and manganese)chromium and molybdenum alloy steels

;1, chromium and molybdenum alloy steelschromium alloy with 1.00 percent carbónnickel, chromium nnd molybdenum alloy steel (with a d i fbetween these ulcmcnts than contained in the 43XX al-

to a nickel, chromiuin, molybdenum allpy containing .40

9Ni-4Co.30C.30 percentcobalt in the

is a specific trade ñame assigned to a nickel - cobalt alloy withcarbón. The 9 and 4 reí?cr to the nominal percentajes of nickel and

alloy.

The normally used low alloyshown. Use of these alloys

steels andis limited

tlieir applicable strength ranges areto the strength ranges shown.

C51-84-546-01Sec B 32

9034ÍMAY 02 1984

LOW ALLOY STEELS AND THEIRAPPLICABLE STRENGTH RANGES

ALLOY

4340

4330M

9Ni-4Co-.30C

4340M

STRENGTH RANGE (KSI)

125-145

X

150-170

X

X

160-180

X

180-200

X

X

220 MIN

X

X

275-300

X

JUN 08 1987Seo D

STEEL ALLOYS ANO TEMPERS

C51-84-046-01A

33

HEAT TREATING STEEL

When steel is heat treated its crystalline structure undergoes various phasechanges. This chart shows the various phases for different carbón content tempera-ture combinations. When steel is heated it will pass through these phases. Ifcooled at a slow rate it will go through the same phase changes in the reverse di-rection. However, if a part is quenched in cold water or oil the material cannotdo a complete phase reversal. It will remain as austenite until tempera tures of600°F or below are reached. Mere the austenite begins to transforin into a consti-tuent called martensite which is responsable for the hardness of quenched steels.

Tempering of this steel is necessary to relieve the resulting 'residual stressescaused by the quenching and to impart toughness to the steel in contrast to thebrittleness of martensite. The structure produced by tempering a quenched steel iscalled tempered martensite.

C51-84-571-01 34 9034ÍSec B JUN 08 1987

LIOUIO AND FEHRITE

FERHITE

FERRITE ANDAUSTEHITE

AUSTENITE

AUSTENITE ANDFERRITE

FERHITE

JUN 08 !!18/Siv II

3.0 3.5 1-0 1.5 5.0

WCIGI IT l 'LRCLNT CARHON

LLinuiD

1 I J LCCMENTITE

LIQUID

L.IQUID ANDAUSTENITE

LIDUin ANDCEMENTITE

AUSTENITE ANDCEMENTITE

FEHRITE ANDCEMENTINE

HEAT TREATING STEEL

CSI-8-1-0/1-U1

l'RIMARY STEELS USLD 1N BOEING A1RPLANES

The most w i d e l y used high strength steels are 4330M heat t r e a t e d to 220-240 ksiand 434QM lieat treated to 275-300 ksi. For elevated -tempera ture applications upto 900F, such as aft.engine mpjjnts, 9Ni - 4Co-0. 30C steel h e a t treated to 220-240ksi is used. The 5ucc«atKÍ*euSe of high strength steel is attributed to carefuldesign and stringent m a t e r i a l and process controls.

\'' (, r. ->??*

For bar and forging applications at strength level of 200 ksi or lower, 15-5PHprecipi ta t ion hartlening stainless steel is currently being used in place ofa 11 oy s t e e l , M anufacturing costs are reduced by using 15-5PII and improvedcorrosión resistance is obtained.

For a p p l i c a t i o n s r e q u i r i n g sheet, 15 - 5PH is used for thicknesses of 0.063 indiand ovcr. H o l l i n a of 15-51'H lo t li i cknessc s undur 0.063 inch is not p r a c t i c a ! ,lio til 1 7 -<1 1>̂ | and 17-7 P̂ ( a 1 ) oy:> con Ui l n ilt; 1 t;i f c r r i ti: i nc I us i ons wh i cli causeuns tabl e transverso mechan i c a 1 propc r t i es . SÍ nce Lli i s i s a mi ñor prob 1 c.w i n Lhot li i n n¡¡ uyi;i) I 7 - 7 I'II l S iisml i n LltJCKllCSStiS luí 1 o u O . OÍJ 3 i ncli ¡uní i s of IUIL a I 1 out,'tlas a s u b s t i t u t e for 15-51*11 in gauges up to 0.10 inch.

300 se r i (>s JI..H.S tt;n i t i c s t a i n l e s s steel sheet .,.„ t, .,„„,, ... ~ ,._,„„ ,. ~. ,„„j th appl i ca t i ons w lie re cor ros í on or hyg i ene c once rus díctate m a t e r i a l

needs, 4 1 3 0 a n i l ' 1 3 4 0 a l l o y s i e o l s h c e tcons t rúe t i on.

ni a t e r í a i s are used for lowerconce rus

m a t e r i a l is ra reí y used in a i r c r a f t

Tb e 727, 737 and 747 use 21-6-9 ¡insten i t i c stainless steel for liydraulic tubingappli catiónS, 17 - 4 IMI preci pi ta t ion hardening stainless stee) i nves tmen t cast-ings h e a t t r e a t e d to 150 ksi or 180 ksi m i n i m u m are also used where a p p l i c a b l e .

C51-84-541-01CSec B 36

9034ÍMAR 03 1986

C

STEEL USAGE ON BOEING AIRPLANES

ALLOYS

4340M

4330M

9NI-4CO-0.30C

15-5PH

2 I - G - 9304/321/347

15-5PH

17-7PH

304/321/347

17-4PH

(KSI)STRENGTH

275-300

220-240

220-240

180-200150-170

I42 -1G275 MIN.

180-200150-170

180-200150J70

75 MIN.

180-200150-170

FORMS

BAR AND FURGING

BAR AND FORGING

BAR ANO FORGING

STAINLESS S T E E LBAR AND F O R G I N G S

TUBING

SHEET

SHEET

SHEET

CASTINGS

APPLICATIONS

LANDING GEAR COMPONENTSFLAP TRACKS. FLAPCARRIAGES, FITTINGS

AFT ENGINE MOUNTS

ACTÜATORS, ROD ENDS,FITTINGS, MECHANISMS

IIYDRAULIC SYSTEMS,INSTRUMENT LINES

LAVATORIES AND GALLEYS,DOOR THRESHOLDS, STRAPS

LAVATORIES AND GALLEYS,DOOR THRESHOLDS, STRAPS

LAVATORIES AND GALLEYS,DOOR THRESHOLDS, STRAPS

CONTROL LEVERS,FITTINGS, HOUSINGS

'V

USAGE RATIONALE

HIGH STRENGTH TO WEIGHTRATIO AND HIGH MODULUS OFELASTICITY

ELEVATED TEMPERATURESTABILITY AND HIGH STRENGTH

CORROSIÓN RESÍSTANLEAND HIGH MODULUS

CORROSIÓN RESISTANCE.FABRICABILITY. ANDHIGH STRENGTH

CORROSIÓN RESISTANCE,HIGH STRENGTH,AND FABRICABILITY

UTILIZED WHEN THICKNESSISLESSTHAN 0.063

FABRICABILITY, HYGIEÑIC NEEDS

CORROSIÓN RESISTANCE,AND FABRICABILITY

MR 1 1983>ec D

PRIMARY STEELS USED IN BOEING AIRPLANES

C51-84-041-01A

37

STEEL ALLOY REWORK PRECAUTIONS

The following precautions must be observad when doing rework operations on steelparts.

\Stress Concentrations

Since most steel parts are highly stressed localized stress concentrations areundesirable and should always be removed.

Hydrogen Embrittlement

Do not introduce hydrogen into the part. If any question exists as to its in-troduction the part must be baked at 375°F for at least 3 hours. This tempera-ture, incidentally, will not harm either paint, or shot peening.

Untempered Martensite

Caution must be exercised whilst reworking the low alloy carbón steels so as toprevent the formation o*f untempered martensite or the generation of undesirableresidual tensile stresses. Any metal removal should be done by hand or withslow speed handheld power tools.

The processing of steel parts is very critical and must be done in the propersequence. The engineer must spell out exactly what work is to be done includitemperature and time limits.

C51-84-551-01 46 9034ÍSec B MAY 02 1984

• STRESS CONCENTRATIQNS

• HYDROGEN EMBRITTLEMENT

• UNTEMPERED MARTENSITE

• STRICT PROCESS CGNTROLS

MAY 02 1984

Süc B

47

STEEL ALLOY REWORK PflECAUTIONS

C51-84-05101

FASTENERS

55

FASTENERS

Fasteners are classified in two basic types; removable and permanent.

Removable fasteners consist of bolts or screws installed with núes or nut plates.Such fasteners inay be removed and reinstalled.

Permanent fasteners consist of hex-drive bolts (Hi-Loks), Lockbolts and Rivets.This type of fastener must have one element of the system destroyed in order toremove it, therefore it is not reusáble.

Removable Fasteners:

Within the removable fastener category are fatigue rated,rated bolts.

tensión rated. and shear

Fatigue rated bolts have 12 point protruding heads with long threads. They areavailable in strength ranges of 160 to 220 KSI tensile strength. Materials arealloy steel, GRES (A286, Inconel 718), 6AL4V titanium or H-ll steel.

Shear and tensile rated bolts may have hex, 12 point or countersunk heads with longthreads for the tensile and short threads for the shear rated. Materials optionsare the same as for the fatigue rated bolts. All Boeing standard bolts have rolledthreads.

Fasteners that are fully threaded, regardless of head style, are usually consideredscrews. Screws are available with hex heads, pan (round) head, flush heads orsocket heads. Recesses are Phillips, Mi-Torque or hex (Alien). Materials arealloy steel, GRES, titanium or aluminum. Strength levéis to 160 KSI tensile and 95KSI shear are available.

Note that screws are not used for structural load transfer.

C51-84-501-01DSec B

56 9033ÍJUN 08 1987

COUNTER SUNKHEAO BOLT

SHORT THREADS

\

LONG THREAD (TENSIÓN)SHGRT THREAD (SHEAR)

SHQRT THREADS

— 1

12 PT MEAD BOIT - LONG THREAD (TENSIÓN)SHORT THREAD (SHEAR)

LONG THftEADS

pp

HEX HEAD BOLTS - LONG THREAD (TENSIÓN)SHGRT THHEAD (SHEAH)

12 POINT HEAD FATIQUE-TENSION BOLT

ALL "BAC" BOLTS ARE PunCHASEOWITH ROLLEO THREADS.

JUN 08Sí:c B

57

FASTENERS

C51-84-001-01C

IIARD FASTENER ALLOYS

The hard fastener alloys together witli the applicable shear and tensilestrengths are summarized for convenience.

CS1-84-552-01 9034ÍSec B 58 MAY 02 1984

ALLOYS'

STEEL

8740/4340

H 11

CRES

A286

PH 13-fl MO

INCONEL 718

TITANIUM

'6AL4V

. MÍNIMUM RATEO STRENGTH - KSI

SHEAR

95

125

95/110

125

102/125

95

TENSIÓN

160

220

160/200

220

180/220

160

MAR 03 1U8G

Stv H

59

HARO FASTENER A L L O Y S

C51 84 052 O ÍA

NUTS/NUT PLATES

Nuts are generally classed as tensión or shear. Tensión nuts are available instrengths of 180 or 220 KSI. Shear nuts are available in 125 KSI strength.Nuts are selected to have a tensile strength equal to or greater than the matingbolt or screw. Nut plates are used in "cióse outs" or other places with limitedor no access. They are attached with rivets. Nutplates are predominately inshear applications and are predominately of 125 KSI strength with a limited num-ber rated at 160 KSI.

CS1-84-S02-01A 3457CSec B 60 MAR 01 1983

TENSIÓN NUT SHEAH NUT

NUTS

NUTPLATES

OCT 24 1383

Set: B

NUTS/NUTPLATES

C5I-84-002-OIA

61

PERMANENT FASTENERS

Hi-Loks, called hex-drive bolts by Boeing, are installed with collars having afrangible hex that "shears off" at a predetermined torque valué. The collar has nomeans of removal other than destruction. One advantage is that no torque wrenchesare required for installation. Self-locking nuts can be, and sometimes are, usedin place of collars. Materials f.or the pins are titanium, alloy steel, GRES, andaluminum. Collars for Hi-Loks are of aluminum, 300 series GRES and A286 GRES.

Lockbolts are optional to shear Hi-Loks. The lockbolt is inherently fluid tight,including fuel. The tensión lockbolt uses an aluminum collar and is lighter thanthe tensión Hi-Lok, which uses a GRES collar. Lockbolts are available in titanium,alloy steel and A-286 GRES. Pulí type lockbolts require more clearance for instal-lation tooling than Hi-Loks.

C51-8-1-503-01B c^ 9033ÍSec B JUN 08 1987

LOCK80LTS HI-LOKS

TENSIÓN - PROTRUDING MEAD

TENSIÓN- FLUSH HEAO

fflTENS1QN-PROTRUDING MEAD

h-TENSIÓN - FLUSH MEAD

SHEAR - PROTRUQING MEAD SHEAR - PROTRUD1NG MEAD

Ili 1SHEAR - REOUCED FLUSH HEAO SHEAR - REDUCCD FLUSH HEAD

JUN 08 1987

Soc B63

PERMANENTFASTENEflS

C51-840G301B

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For metal plástic,find wood. Al!iirstall wilh?!3ndar-í tools

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'/érsionsSpecificíi,./,- .^e

- valia Wo

industrialf asten-írsConstrocfipn

The ilhtstraiion below, depicts lypical and common aircraft ( AN and ÑAS ) typeand their ideniilying niarkings.

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*

Buyin rjulk ana.sai/e! Pins of alltyne*1. r.f-rieí; jnd

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AVRlAKOARfs -:LI. ¡SOL*

Ai :.;; '..vj'--- A: - f

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materials innovation

Hex Bott Identification Cuide

Hardware Menú | Products and Services DirectoryBump Thread Metric Machine ScrewPatentad prevailmg lock thread Enhanced S reusable locking action Rnd everythmg vou need to know about Screw Machine Produc

• , .nump-tlread con _ScrewM achine. Machines-Diré ct.com

Note: Some bolts share identical head Identification and have significanliy differem strengths.

IdentificationGrade Mark

^S1 s X. JV >^^

fT»r ii 1k ¿

^^.̂X

í??^,<^I jv^>7^'• u.!> i!v,,x

Specifícation

S.\EJ429•!c 5

ASTM A44Q

SAE J429Grade 5.!

SAh J42*íGrade 5.2

ASI'Vl A325-(.'. \

ASTM A325Type 2

Description

Bolts, Screws,Studs

fSems

Bolts,Screws,

Studs

High StrengthStructural Bolts

Higli StrengthStructural Bolts

Material

Médium CarbónSteel

Low or MédiumCarbón Steel

Low Carbón

Médium Carbón

Low Carbón

ProofLoad

S5 C74. •' '

-

85.000

.

S5.000

VieldStrengthMin (psi)

92,000thru 8 1 ,000

92,000

92,000thru 81,000

92,000

-- TensStren;Min (|

'

1 20,0

.