All data is for information only------(<---links)
PRODUCT DATA of AA7149-T73
MaterialAA7149-T73
General Information7049 is basically a forging alloy. It is heat treatable with very good resistance to stress corrosion cracking
Processing and AssemblySolution heat treated and then artificially overaged in order to achieve the best stress corrosion resistance
EXPERIENCE IN PRACTICE
Equivalent DesignationsAA 7149
PHYSICAL PROPERTIES
Specific Gravity2.8
Magnetic PropertiesNonmagnetic
ELASTIC PROPERTIES
Tensile Modulus72 GPa
Shear Modulus27 GPa
Poisson Ratio0.33
THERMAL PROPERTIES
Thermal Conductivity155 W/m.K
Thermal Expansion Coefficient23.4 μstrain/°C
Melting Range477 to 635 °C
Specific Heat0.864 J/g.K
RELEVANT PROPERTIES FOR USE IN SPACE COMMUNITY
General Corrosion StatusRequires specific corrosion protection
Stress Corrosion StatusHigh Resistance to SCC: Table 1
Data Quality: Design Data
Bimetallic CorrosionCan be used in a non-controlled environment: Al alloys, Cd
Can be used in a clean room environment: Mg, Sn-Pb alloys (all), Sn, Pb, Zn, Be
Needs specific measures: All others
Test:ECSS-Q-ST-70C Rev.1 Table 5.1
Data Quality: Design Data
MachinabilityThe machinability of 7049 is good in the heat treated state. As with most of the aluminum alloys the use of oil lubricants is recommended during machining.
WeldingWelding of 7049 alloy should be avoided. It may be possible to do TIG welding, but best to consider this as an alloy that is not normally welded.
AgingAging, or precipitation hardening, is done in a 2 step heat treatment. First allow 48 hours at room temperature, followed by 24 hours at 121 C and air cool. Second step is 14 hours aging at 160 C and for 14 hours followed by air cooling.
Atomic OxygenNo effect