[ALUMINIUM NETWORK] For many years, metallurgists have always believed that the age hardening of 6xxx Al-Mg-Si alloys is due to the precipitation of different phases at different stages. The first step is the formation of supersaturation by solution treatment (in-line quenching or off-line quenching). In the solid solution, even if all Mg and Si are dissolved in the α-Al matrix, Mg and Si atoms will be precipitated from the α-Al solid solution during the subsequent aging process (relative to the solution treatment temperature). Come out, the order of its precipitation is as follows:
Supersaturated solid solution (phase) α-Al → Coherent Mg, Si atom group (GP zone) → Semicoherent needle-like Mg, Si atom group β "phase → Semi-coherent rod (bar) The β' phase → non-coherent platelet (plate) β phase, ie the Mg2Si phase with an independent lattice.
In the Mg2Si compound, the atomic ratio of Mg and Si is 2, that is, Mg:Si atom=2, or their mass ratio is 1.73, and the ratio of 2 parts of magnesium atomic weight to one part of silicon atomic weight is 7.73. For this reason, both metallurgists and extrusion workers think that and always obey the law that the composition of the alloy conforms to an atomic ratio of 2, it is possible to make Mg and Si all form Mg2Si, and produce a greater strengthening effect, which is better The comprehensive performance.
However, the past 10 years of research and extrusion practices have shown that Mg:Si (atomic ratio) is close to 1 in the βâ€phase and β′ phase. Therefore, when Mg:Si (atomic ratio)=1 in 6xxx alloy, Better T5 and T6 performance can be obtained.The new 6xxx alloy recently put on the market was developed based on this principle. For example, the AA6360 alloy registered in the American Association Corporation in 2001 is a typical representative of this kind of alloy, its composition (W%) : 0.35~0.8 Si, 0.10~0.30Fe, 0.15Cu, 0.02~0.15Mn,
0.25 to 0.45 Mg, 0.05 Cr, 0.10 Zn, 0.10 Ti, other impurities, a single 0.05, total 0.15, and the remainder Al. The total content of Mg and Si in 6360 alloy is only 14% lower than that of 6063 alloy, which can be said to be almost equal, but its Si content is 44% higher than that of 6063 alloy and its magnesium content is 48.2% lower than that of 6063 alloy.
Due to this design of the 6360 alloy composition, the ratio of Mg atoms to Si atoms in the β′ phase formed in the early stage of the aging process and the ratio of Si atoms in the β′ phase is equal to 1, and the lattice distortion is large, so that the alloy is maintained with the 6063 alloy. The equivalent strength has even more other properties.Compared with the 6063 alloy 6360 alloy and the advantages are:
l 20% faster extrusion speed for solid profiles and 40% higher for hollow profiles such as pipes;
l The mechanical properties of 6360-T6 alloy are comparable to that of 6063-T6 alloy; their physical and chemical properties are the same;
l Its extrusion process and finishing process are the same as those of the 6063 alloy. The melting and casting process is the same, and the surface treatment properties are the same.
In view of the above reasons, the extrusion energy consumption of 6360 alloy is lower than that of 6063 alloy, and the production efficiency will be higher by more than 20%. Enterprises interested in this may wish to give it a try, perhaps the benefit will be better.
Neon Sign,Neon Lights,Neon Light Signs,Neon Lights For Room
Guangdong Yuansheng Ad.&Lightings Co,Ltd. , https://www.pilottsignonline.com