Custom Shape Extruded Aluminum Parts Al7075 Alu Extrusion Profile CNC Machining

Modern casting aluminum alloys can be divided into 4 series according to the main elements added, namely: aluminum-silicon system, aluminum-copper system, aluminum-magnesium system and aluminum-zinc system.For these 4 series, there are corresponding alloys and alloy grade marks in various countries.China adopts ZL+3 digit marking method, the first digit indicates the alloy system, of which: 1 indicates the aluminum-silicon alloy system, 2 indicates the aluminum-copper alloy system, 3 indicates the aluminum-magnesium alloy system, and 4 indicates the aluminum-zinc alloy system, and the second and the third digits indicate the alloy serial number.China's several typical casting aluminum alloy as shown in the table, according to the use of alloy characteristics can be divided into: heat-resistant casting aluminum alloy, airtight casting aluminum alloy, corrosion-resistant casting aluminum alloy and weldable casting aluminum alloy

Aluminum-silicon alloy

Usually silicon content of 4% to 13%, also known as "silicon aluminum Ming" alloy.The casting performance is the best, the tendency to crack is very small, the shrinkage rate is low, there are very good corrosion resistance and airtightness as well as sufficient mechanical properties and welding performance.This system of alloys in the industrial application of aluminum - copper alloys later, but in 1920 found that can be metamorphic treatment, so that the organization and performance of the alloys have been improved to broaden the scope of use, in the amount of almost 50% of the casting of aluminum alloys.Aluminum-silicon alloys can be divided into eutectic, sub-eutectic, over-eutectic and add copper, magnesium, manganese and other complex eutectic alloys. zl102 alloy is a typical binary eutectic alloys, eutectic temperature of 577 ℃, eutectic composition of 12.6% Si, the eutectic temperature of the α-solid solution in the dissolution of 1.6% Si, dissolved at room temperature about 0.05% Si; β-phase for the aluminum dissolved in the silicon in the solid solution, the solubility of itsVery small, so the eutectic organization for the α + Si two-phase composition.Multi-alloy organization, in addition to α and silicon, there are θ (CuAl2), W (AlxMg5Si4) and other phases (see the phase of aluminum alloys).Aluminum-silicon alloys containing copper can be heat-treated for strengthening, but have poor corrosion resistance.The shape of the silicon phase in the alloy has a significant effect on strength and plasticity, and the organization and properties of the alloy are improved by metamorphic treatment (addition of sodium or antimony to the melt) to sphericalize the silicon phase.Over eutectic alloys in the coarse primary crystalline silicon is harmful to the mechanical properties and cutting performance, often adding phosphorus, the formation of AlP compounds, so that the primary crystalline silicon refinement, reduce its harmful effects.