Research on microstructure in as-cast 7A55 aluminum alloy and its evolution during homogenization

Lv, Xinyu; Guo, Erjun; Li, Zhihui; Wang, Guojun

doi:10.1007/s12598-011-0446-7

Cited by 26 publications

(5 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It can be seen that the grain boundaries are decorated by large, irregular eutectic phases and intermetallic particles that had a detrimental effect on mechanical properties of the alloy. Xinyu et al, [12] reported that plenty of heterogeneous MgZn precipitates formed during the fast cooling of the ingots, mostly observed around the grain boundaries. Alloying element (MgZn) precipitated gradually from matrix during the fast cooling stage, as these two elements are within the main chemical composition of AA 7075 alloy as shown in Table 1 and according to literatures [7,15] MgZn phase probably responsible for strengthening of the Al alloy after heat treatment.…”

mentioning

confidence: 99%

The Role of Direct Chilling, Retrogression and Reaging Treatment on Mechanical Properties of High Strength Aluminum Alloy

Naeem

Mohammed

Khairel

et al. 2013

AMR

View full text Add to dashboard Cite

The effect of retrogression and reaging heat treatment on microstructure evolution andmechanical properties of 7075 Al alloy in direct chilling casting process was investigated. The subsequent heat treatment process comprised pre-aging at 120°C for 24 h, retrogression at 180°C for 30 min, and then reaging at 120°C for 24 h. By this three-step process, the mechanical properties of the chilled casted samples were substantially improved. The samples retain their high strength at T6 level. They gave yield strength up to 290 MPa, ultimate tensile strength of 386 MPa and elongation of 5.9%. The average value of multiple Vickers hardness tests results were in the range of 210 Hv. The direct chilling process followed by retrogression and reaging heat treatment yielded casts of fine and uniform microstructure as opposed to the microstructure of samples casted by the conventional process.

show abstract

mentioning

confidence: 99%

The Role of Direct Chilling, Retrogression and Reaging Treatment on Mechanical Properties of High Strength Aluminum Alloy

Naeem

Mohammed

Khairel

et al. 2013

AMR

View full text Add to dashboard Cite

show abstract

“…As a result, the calculated strength from the solid solution strengthening effect is about 73.0 MPa. This means that, after solution treatment, the yield strength will increase [8,[11][12][13][14][15][18][19][20][21][22][23][24][25][26][27] by 73.0 MPa, which is approximately equal to the experimental increase of 66.0 MPa. With the disappearance of the T phase and the absence of the S phase, the ductility of the alloy was also significantly improved, which is consistent with the results of other articles [14,27,29].…”

Section: Effect Of Solution Treatment On Yield Strength and Impact Toughnessmentioning

confidence: 88%

Effects of Solution Treatment on the Microstructure, Tensile Properties, and Impact Toughness of an Al–5.0Mg–3.0Zn–1.0Cu Cast Alloy

Tang

Wang

Luo

et al. 2020

Acta Metall. Sin. (Engl. Lett.)

View full text Add to dashboard Cite

This study investigates the effect of solution treatment (at 470 °C for 0-48 h) on the microstructural evolution, tensile properties, and impact properties of an Al-5.0Mg-3.0Zn-1.0Cu (wt%) alloy prepared by permanent gravity casting. The results show that the as-cast microstructure consists of α-Al dendrites and a network-like pattern of T-Mg 32 (AlZnCu) 49 phases. Most of the T-phases were dissolved within 24 h at 470 °C; and a further prolonging of solution time resulted in a rapid growth of α-Al grains. No transformation from the T-phase to the S-Al 2 CuMg phase was discovered in this alloy. Both the tensile properties and impact toughness increased quickly, reached a maximum peak value, and decreased gradually as the solution treatment proceeded. The impact toughness is more closely related to the elongation, and the relationship between impact toughness and elongation appears to obey an equation: IT = 8.43EL − 3.46 . After optimal solution treatment at 470 °C for 24 h, this alloy exhibits excellent mechanical properties with the ultimate tensile strength, yield strength, elongation and impact toughness being 431.6 MPa, 270.1 MPa, 19.4% and 154.7 kJ/m 2 , which are comparable to that of a wrought Al-6.0Mg-0.7Mn alloy (5E06, a 5xxx aluminum alloy). Due to its excellent comprehensive combination of mechanical properties, this cast alloy has high potential for use in components which require medium strength, high ductility and high toughness. Keywords Al-Mg-Zn-Cu cast alloys • T-Mg 32 (AlZn) 49 phase • S-Al 2 CuMg phase • Impact toughness • Mechanical properties

show abstract

“…The composition of intermetallic phases in Al-Zn-Mg-Cu alloy is complicated due to the variety of elements and the high main alloying element content. According to previous research reports, numerous intermetallic phases formed in as-cast alloy, including T(AlZnMgCu), θ(Al2Cu), S(Al2CuMg), η(MgZn2) and Al7Cu2Fe, etc [9][10][11][12][13]. The second phases with different types in as-cast alloy are not the same with the change of main alloying elements content.…”

Section: Introductionmentioning

confidence: 92%

Effect of Zn/Mg Ratio on Microstructure Evolution of Al-Zn-Mg-Cu Alloys during Homogenization

Yin

et al. 2022

KEM

View full text Add to dashboard Cite

The effect of Zn/Mg ratio on the as-cast microstructure and its evolution during homogenization of Al-Zn-Mg-Cu alloys was investigated by optical microscopy (OM), differential scanning calorimetry (DSC), scanning electron microscope (SEM) and X-ray diffraction (XRD). Experimental results showed that serious dendritic segregation existed in the as-cast microstructures while the second phases were mainly AlZnMgCu phase and Al2Cu phase. With the Zn/Mg ratio increasing from 1.5 to 2.0, the area fraction of AlZnMgCu phase decreased from 2.85% to 2.53%, which was attributed to the content of Mg element. Non-equilibrium eutectic phases dissolved into the matrix during homogenization and phase transformation from AlZnMgCu phase to Al2CuMg phase (S phase) was observed in low-Zn/Mg ratio alloy and mid-Zn/Mg ratio alloy. In the high Zn/Mg ratio alloy, the eutectic AlZnMgCu phase directly dissolved into the matrix during the homogenization, and no transformation from AlZnMgCu phase to S phase was found. A higher number of S phases appeared in low-Zn/Mg ratio alloy during homogenization treatment compared with mid-Zn/Mg ratio alloy with a regime of 465°C/24h. It could be inferred that low-Zn/Mg ratio alloys had a stronger phase transformation tendency from AlZnMgCu phase to S phase. Increasing the homogenization treatment temperature could impair the transition tendency from AlZnMgCu phase to S phase.

show abstract

Research on microstructure in as-cast 7A55 aluminum alloy and its evolution during homogenization

Cited by 26 publications

References 12 publications

The Role of Direct Chilling, Retrogression and Reaging Treatment on Mechanical Properties of High Strength Aluminum Alloy

The Role of Direct Chilling, Retrogression and Reaging Treatment on Mechanical Properties of High Strength Aluminum Alloy

Effects of Solution Treatment on the Microstructure, Tensile Properties, and Impact Toughness of an Al–5.0Mg–3.0Zn–1.0Cu Cast Alloy

Effect of Zn/Mg Ratio on Microstructure Evolution of Al-Zn-Mg-Cu Alloys during Homogenization

Contact Info

Product

Resources

About