Chemistry: Sib txawv Strengthening Systems
7075 yog lub tshav kub- kho tau Al-Zn-Mg-Cu alloy. EN 573-3 qhia txog 5.1-6.1% Zn, 2.1-2.9% Mg thiab 1.2-2.0% Cu, nrog Cr hauv 0.18-0.28% ntau yam, Si mus txog 0.40%, Fe mus txog Mn mus txog 0.50%, Fe mus txog 0.50% 0.20%. Cov zinc thiab tooj liab cov ntsiab lus tsim MgZn2 thiab Al2CuMg precipitates uas muab cov hlau nws lub zog tshwj xeeb . 6061 zaum hauv tsev neeg Al-Mg-Si: 0.8-1.2% Mg, 0.40-0.8% Si, 0.15-0.40% Cu thiab 0.54% Cr. Tsawg alloying ntxiv tab sis ib tug huv si, ntau weldable thiab ntau corrosion-resistant matrix.
Mechanical Properties muab piv
| Khoom | 6061-T6 / T651 | 7075-T651 |
|---|---|---|
| Tensile zog (tseem ceeb) | txog 310 MPa | txog 570 MPa |
| Yield zog, 0.2% (tus qauv) | Qhov siab tshaj 276 MPa | txog 500 MPa |
| Elongation (ntev) | txog 10-12% | txog 11% |
| Hardness | cav 95hb | txog 150 HB |
| Machineability | zoo | ncaj ncees |
| Weldability | zoo (filler 4043 / 5356) | pluag, feem ntau tsis welded |
| Corrosion kuj | zoo heev | nruab nrab, xav tau kev tiv thaiv |
ASTM B209 yog cov lus qhia dav dav rau phaj ntawm ob qho tib si alloys; 7075-T651 phaj rau aerospace siv yog ntxiv los ntawm AMS 4045, uas kho cov muaj pes tsawg leeg thiab cov neeg kho tshuab txais kev txwv rau 5.6Zn-2.5Mg-1.6Cu-0.23Cr muaj pes tsawg leeg.
Lub cev muaj zog
| Khoom | 6061-T6 | 7075-T651 |
|---|---|---|
| Qhov ntom | 2.70 g / cm3 | 2.81 g / cm3 |
| Elastic modulus | cav 69gpa | ua 72gpa |
| Hom thermal conductivity | Txog 167 W / mK | Txog 130 W / mK |
| Melting ntau | 582-652 C | 477-635 C |
Qhov ze dua atomic packing ntawm 7075 matrix kuj nce hluav taws xob tsis zoo, uas yog qhov tseem ceeb thaum lub sij hawm muab ob npaug rau tus neeg xyuas pib lossis EMI txoj kev.
Corrosion, qaug zog thiab kev pabcuam tus cwj pwm
6061 resists atmospheric, tshiab- dej thiab tshuaj lom neeg mob me yam tsis muaj kev tiv thaiv ntxiv thiab tsis ua rau muaj kev ntxhov siab -corrosion cracking nyob rau hauv ib txwm tempers. 7075 muaj qis dua corrosion kuj thiab, nyob rau hauv ib co tempers, yog raug rau kev nyuaj siab -corrosion cracking; Cov chaw pabcuam raug tiv thaiv los ntawm anodising lossis primer thiab tsis siv rau qhov chaw muaj zog tensile kev ntxhov siab ua rau ntub dej lossis chloride-cov kabmob ib puag ncig. Ntawm qhov qaug zog, 7075 muaj lub zog qaug zog ntau dua ntawm qhov sib piv ntawm kev ntxhov siab, uas yog vim li cas nws ua rau cov khoom siv dav hlau thauj khoom hnyav, thaum 6061 raug xaiv qhov kev thauj mus los yog nruab nrab thiab nruj lossis corrosion kuj tswj.
Kev Taw Qhia Xaiv
Siv 7075-T651 thaum tus qauv tsim muaj zog- lossis qhov hnyav- tseem ceeb thiab qhov tseem ceeb thiab cov khoom yog machined los ntawm cov khoom nyob rau hauv ib puag ncig tiv thaiv: airframe fittings, pwm thiab tuag, high-load brackets, sib xeem khiav Cheebtsam thiab tiv thaiv hardware. Siv 6061-T6 los yog T651 thaum lub qhov yog welded, anodised rau cov tsos, raug huab cua los yog tshuaj, los yog thaum ib tug nruab nrab lub zog theem ntawm tus nqi qis thiab zoo machinability yog txaus: jigs, fixture daim hlau, thav duab, marine fittings thiab general engineering Cheebtsam.
Cov lus nug nquag
Q:Puas yog 7075-T651 ob zaug muaj zog li 6061-T6?
A: Hauv kev nro, yog - lub zog tensile ib puag ncig yog nyob ib puag ncig 570 MPa tiv thaiv txog 310 MPa - tab sis qhov piv yog qis dua hauv kev qaug zog thiab nruj, qhov twg elastic moduli txawv li ntawm 4%.
Q:7075 puas tuaj yeem welded?
A: Feem ntau tsis yog rau kev tsim kho; cov alloy yog rhiab heev rau kub tawg thiab kub- cuam tshuam cheeb tsam lub zog poob, yog li 7075 qhov chaw yog mechanically fastened los yog bonded.
Q:Cov tshuab hlau twg zoo dua?
A: 6061-T651 tshuab sai dua thiab yoojyim ua kom tiav nrog cov cuab yeej siv tsawg dua; 7075-T651 cov tshuab kom ua tiav zoo tab sis ntawm kev txiav qis qis thiab nrog kev saib xyuas ntau dua rau nti khiav tawm.
Q:Puas yog 7075-T651 xav tau kev tiv thaiv sab nraum zoov?
A: Yog. Anodizing, chromate hloov dua siab tshiab los yog primer system yog siv los txwv pitting thiab txo kev ntxhov siab -kev pheej hmoo corrosion.
Q:Yam qauv twg yuav tsum tau siv daim ntawv xaj khoom?
A: ASTM B209 rau phaj ntawm ob qho hlau alloy, nrog AMS 4045 ntxiv thaum 7075-T651 phaj yog xav tau rau kev txais aerospace.