تأثير اضافة عنصر النيكل على مسبوكة الالمنيوم - نحاس قبل وبعد المعاملة الحرارية

الملخص EN

In this research, the effect of adding pure nickel element in different amounts Al-4%Cu-1.5%Mg) has been studied it (to molten alloy (1-2-3-5%wt) making the heat treatment (T6) which includes solution treatment followed by artificial aging at 220 ºC at different times within the range (5 min.-5 hr.)).

Also the effect of nickel element on the microstructure, the grain size and the phases type which are constructed in the produced alloys by alloying before and after heat treatment by using optical microscope and X-Ray diffraction test device have been studied then the hardness and tensile test were implemented and then the result showed: the alloy with the highest adding rate (5% wt) shows a better response than the other alloys for hardening in longer time period where it have been reached to highest hardness (125 H.V) in time period (4hr) at (220 ºC).

While the empty alloy of nickel reached to highest hardness equals to (112 H.V) in a time period less than (2hr).

The constructed phases in alloys have been specified after adding Ni element, where it indicated to the existence of the phase (Al7Cu4Ni) which is responsible for the slowliness which occurs in the alloy’s response to precipitation hardening procedure which leads to delay (longer time periode) to obtain a higher hardness.

It also found that adding of nickel causes an increase and an improvement in the properties of the tensile strength, yield strength and elongation, which indicates that the presence of the nickel takes two ways part of it dissolve with Aluminum and copper to produce the phase (Al7Cu4Ni) which causes the slowing in the construction of the hardening phase (Al2CuMg), the other part causes refining grains size at the highest temperature degrees causing an increase in the strength and the hardness in a rate which is higher for the alloy’s that contain nickel in a comparison with the empty alloy of nickel.