As you know. our aluminum tile trim/aluminum skirting/led aluminum profile/aluminum decoration profile is made of 6063 aluminum alloy. the aluminum element is the main part. and the rest element would be as below.
And today we will explain the role and influence of various elements in aluminum alloys on the properties of aluminum materials.
copper element
When the aluminum-rich part of the aluminum-copper alloy is 548, the maximum solubility of copper in aluminum is 5.65%, and when the temperature drops to 302, the solubility of copper is 0.45%. Copper is an important alloying element and has a certain solid solution strengthening effect. In addition, CuAl2 precipitated by aging has obvious aging strengthening effect. The copper content in aluminum alloys is usually 2.5% to 5%, and the strengthening effect is best when the copper content is 4% to 6.8%, so the copper content of most hard aluminum alloys is in this range.
Silicon element
When the aluminum-rich part of the Al-Si alloy system is at the eutectic temperature of 577 °C, the maximum solubility of silicon in the solid solution is 1.65%. Although the solubility decreases with decreasing temperature, these alloys are generally not heat treatable. Al-Si alloys have excellent castability and corrosion resistance.
If magnesium and silicon are added to aluminum at the same time to form an aluminum-magnesium-silicon alloy, the strengthening phase is MgSi. The mass ratio of magnesium to silicon is 1.73:1. When designing the composition of the Al-Mg-Si alloy, the content of magnesium and silicon should be configured according to this ratio on the substrate. Some Al-Mg-Si alloys, in order to improve the strength, add an appropriate amount of copper, and at the same time add an appropriate amount of chromium to offset the adverse effect of copper on corrosion resistance.
Al-Mg2Si alloy alloy equilibrium phase diagram The maximum solubility of Mg2Si in aluminum in the aluminum-rich part is 1.85%, and the deceleration is small with the decrease of temperature.
In deformed aluminum alloys, the addition of silicon to aluminum alone is limited to welding materials, and the addition of silicon to aluminum also has a certain strengthening effect.
Magnesium element
The aluminum-rich part of the equilibrium phase diagram of the Al-Mg alloy system, although the solubility curve shows that the solubility of magnesium in aluminum decreases greatly with the decrease of temperature, but in most industrial deformed aluminum alloys, the content of magnesium is less than 6%. The silicon content is also low. This type of alloy cannot be strengthened by heat treatment, but it has good weldability, good corrosion resistance, and medium strength.
The strengthening of magnesium to aluminum is obvious. For every 1% increase in magnesium, the tensile strength will increase by about 34MPa. If manganese is added below 1%, it may supplement the strengthening effect. Therefore, after adding manganese, the magnesium content can be reduced, and at the same time, the hot cracking tendency can be reduced. In addition, manganese can also make the Mg5Al8 compound precipitate evenly, and improve the corrosion resistance and welding performance.
Manganese
The maximum solubility of manganese in solid solution is 1.82% when the eutectic temperature is 658 in the equilibrium phase diagram of Al-Mn alloy system. The strength of the alloy increases continuously with the increase of solubility, and the elongation reaches the maximum when the manganese content is 0.8%. Al-Mn alloys are non-aging hardenable alloys, that is, they cannot be strengthened by heat treatment.
Manganese can prevent the recrystallization process of aluminum alloy, increase the recrystallization temperature, and can significantly refine the recrystallization grains. The refinement of recrystallized grains is mainly due to the hindrance to the growth of recrystallized grains through the dispersed particles of MnAl6 compound. Another function of MnAl6 is to dissolve impurity iron to form (Fe, Mn) Al6, reducing the harmful effects of iron.
Manganese is an important element of aluminum alloys, which can be added alone to form Al-Mn binary alloys, and more often added together with other alloying elements, so most aluminum alloys contain manganese.
Zinc element
The solubility of zinc in aluminum is 31.6% when the aluminum-rich part of the Al-Zn alloy system equilibrium phase diagram is 275, and its solubility drops to 5.6% when it is 125.
When zinc is added to aluminum alone, the improvement of the strength of aluminum alloy under deformation conditions is very limited, and there is also a tendency to stress corrosion cracking, which limits its application.
Zinc and magnesium are added to aluminum at the same time to form a strengthening phase Mg/Zn2, which has a significant strengthening effect on the alloy. When the Mg/Zn2 content increases from 0.5% to 12%, the tensile strength and yield strength can be significantly increased. The content of magnesium exceeds that required for the formation of Mg/Zn2 phase. In superhard aluminum alloys, when the ratio of zinc to magnesium is controlled at about 2.7, the stress corrosion cracking resistance is the largest.
If copper is added to Al-Zn-Mg to form Al-Zn-Mg-Cu alloy, the matrix strengthening effect is the largest among all aluminum alloys, and it is also an important aluminum alloy material in aerospace, aviation industry, and electric power industry.
Post time: Jul-17-2023