Effect Of High Presure Treatment On Microstructure And Properties Of LY12 Aluminum Alloy

In this discourse, the effects of high-pressure treatment on microstructure, mechanical properties and corrosion resistance of the LY12 aluminum alloy were studied. And it was characterized using metalloscope, scanning electron microscope and energy spectrum analysis and x-ray diffraction. At the same time, the effects of parameters in high-pressure treatment on physical mechanism of properties were discussed.Results of the study show that:In the pressure range from 0 GPa to 5 GPa, the Vickers Hardness of LY12 aluminum alloy of high-pressure treatment increased with the rising of pressure value. The Vickers Hardness of LY12 aluminum alloy reached the maximum at 5 GPa. Compared with the untreated original sample, the Vickers Hardness has increased 10%. In the course of high-pressure treatment at high temperature, the Vickers Hardness of LY12 aluminum alloy significantly increased with the rising of the temperature high-pressure treatment and the aging time. The sample with high-pressure treatment at 800℃, 5 GPa reached the maximum in 60 days. Compared with the untreated original sample, the Vickers Hardness has increased 58%. The change low of the Vickers Hardness keep consistent with the change low of compressive strength; In the thermal range from room temperature to 400℃, the compression yield strength of LY12 aluminum alloy of high-pressure treatment fall down with the rising of pressure value and the plastic increased. Compared with the sample of high-pressure treatment at low temperature, the compression yield strength of LY12 aluminum alloy of high-pressure treatment increased in the thermal range from 500℃to 900℃, and the plastic reduced; The main reason of begetting change of the corrosion potentials is the pressure value of high-pressure treatment in the pressure range from 0 GPa to 5 GPa and the thermal range from room temperature to 400℃. The corrosion potentials of LY12 aluminum alloy of high-pressure treatment increased with the rising of pressure value. With the rising of the temperature, Compared with the effect of pressure value, the effect of temperature of the corrosion potentials played a major role. Compared with the original sample, the corrosion potentials of LY12 aluminum alloy is higher at 700℃. Compared with the untreated original sample, the corrosion potentials has increased. And the corrosion potentials increased when the pressure value reduced. When the temperature arrives melting 1000℃, the corrosion potentials of different pressure value are increased together and keep stable at -0.25 v.