Microstructure and materials characterisation of the novel Al–Cu–Y alloy

Abstract

The microstructure, hot cracking susceptibility, and mechanical properties of a novel Al–Cu–Y alloy were investigated. The Al–4.7Cu–1.6Y alloy demonstrated very good casting properties, hot cracking susceptibility that is similar to Al–Si–Mg alloys. Analysis of the solidification process showed that the primary Al solidification is followed by the eutectic reaction Liquid→ τ1(Al8Cu4Y)+Al and the peritectic reactions Liquid+ τ6(Al,Cu)11Y3)→Al+ τ1(Al8Cu4Y) (612°C) and Liquid+ η(AlCu)→ τ1(Al8Cu4Y)+ θ(Al2Cu) (595°C). The τ1(Al8Cu4Y) eutectic phase demonstrated high thermal stability during homogenisation treatment. The recrystallisation temperature was in the range 250–350°C after rolling with previous quenching at 540 and 590°C and without heat treatment. The recommended annealing mode for material in the as-rolled condition is 100°C for 1 h: YS = 273 MPa, UTS = 305 MPa and El. = 6.6%.

Hot Deformation Behavior of Novel Al-Cu-Y(Er)-Mg-Mn-Zr Alloys

“…A finer grain structure (25-40 µm) was seen in AlCuYMg1 and AlCuErMg1 due to higher Ti content [22]. The microstructure of the Al-Cu-Y and Al-Cu-Er system based quasibinary alloys with Zr, Mn, Ti, Mg addition was investigated in detail in previous works [8][9][10][11][12][13][14][15][16] [8][9][10][11][12][13][14][15][16]22,23] with a size of 0.5-4 µm were present in the microstructure of the investigated alloys in the as-homogenized state. The average intermetallic phase particles size was 1.5 ± 0.5 µm.…”

“…A finer grain structure (25-40 µm) was seen in AlCuYMg1 and AlCuErMg1 due to higher Ti content [22]. The microstructure of the Al-Cu-Y and Al-Cu-Er system based quasibinary alloys with Zr, Mn, Ti, Mg addition was investigated in detail in previous works [8][9][10][11][12][13][14][15][16]. The aluminum solid solution (Al) and a fine eutectic ((Al)+Al8Cu4Y) and ((Al)+Al8Cu4Er) were the main structure parts of the Al-Cu-Y and Al-Cu-Er system based quasibinary alloys in the as-cast state.…”

“…The aluminum solid solution (Al) and a fine eutectic ((Al)+Al8Cu4Y) and ((Al)+Al8Cu4Er) were the main structure parts of the Al-Cu-Y and Al-Cu-Er system based quasibinary alloys in the as-cast state. The low fraction of the AlCu, Al3Er, (Al,Cu)11Y3 formed during solidification in the ternary alloys [8,9,13]. Manganese and magnesium additions led to formation of the Al25Cu4Mn2Er, Al25Cu4Mn2Y and Mg2Si phases [12,16,22,23].…”

“…Novel Al-Cu-Y [8][9][10][11][12] and Al-Cu-Er [9,[13][14][15][16] alloys demonstrate enhanced casting and mechanical properties due to a wide solidification range [8,9,11,[17][18][19][20] and particle dispersion and thermally stable structure [8][9][10][11][12][13][14][15][16]. Perspective quasibinary Al-Cu-Ce alloys also exhibit such properties [21].…”

The Phase Composition and Mechanical Properties of the Novel Precipitation-Strengthening Al-Cu-Er-Mn-Zr Alloy

“…Ternary alloys with a 4/1 atomic rotation of Cu/Er from the quasi-binary section Al-Al 8 Cu 4 Er have a narrow solidification range (less than 40 • C) [18,19] compared with that of the Al-Cu alloys (about 100 • C) [20][21][22][23], which can provide the same casting properties found in Al-Si-Cu alloys [20][21][22][23][24][25]. Investigations of the quasi-binary alloys of the Al-Cu-Y and Al-Cu-Ce systems demonstrated low hot cracking susceptibility [26][27][28]. Moreover, the fine eutectic Al 8 Cu 4 Er phase demonstrates good size stability during high temperature homogenization treatment [18,19].…”