Age Hardening Behavior in Al-8Zn-2Mg-2Cu Wrought Aluminum Alloy

2012 ◽  
Vol 710 ◽  
pp. 527-532
Author(s):  
V. Anil Kumar ◽  
Raghavendra R. Bhat ◽  
Romesh C. Sharma
Keyword(s):  
Heat Treatment ◽  
Aluminum Alloy ◽  
Aging Time ◽  
Large Scale ◽  
Aluminum Matrix ◽  
High Strength ◽  
Age Hardening ◽  
Stable Phase ◽  
Conductivity Measurements ◽  
Peak Aging

Aluminum alloys based on Al-Zn-Mg-Cu system classified under high strength light alloys, find a large scale application in aerospace sector. In the present study, heat treatment of an Aluminum alloy with Al-8Zn-2Mg-2Cu wt.% (AA7449) was carried out. Heat treatment parameters were optimized based on hardness and conductivity measurements. The mechanisms of strengthening in primary and secondary aged states are explained using hardness and conductivity measurements. Conductivity generally showed an increasing trend with increase in aging time, which could be attributed to decrease in the lattice distortion of the Aluminum matrix with increase in aging time. The dissolution of GP zones and formation of other metastable phases like η’ and stable phase like η were found to reduce the supersaturation in the matrix as the precipitation growth and coarsening processes are completed during overaging. Transmission electron microscopy (TEM) study was carried out to confirm the peak-aging regime. Selected Area Diffraction (SAD) patterns were recorded where GP zones and η’ precipitates were observed in the bright field images to establish their nature. The mechanical properties were correlated with the TEM observations and was suggested that a critical distribution of GP zones and η’ precipitates is essential to achieve peak strength in Al-Zn-Mg alloys.

Influence of Three-Step Aging Heat Treatment on Properties of 7A04 Aluminum Alloy

2011 ◽  
Vol 704-705 ◽  
pp. 645-649
Author(s):  
Qiu Ze Li ◽  
Lei Xu ◽  
Ji Xiao Song ◽  
Jing Han ◽  
Xing Min Huang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Aging Process ◽  
High Strength ◽  
Aging Heat Treatment ◽  
Peak Aging ◽  
Low Temperature Aging ◽  
Mechanical Properties And Corrosion ◽  
Temperature Aging

Aiming at traditional peak aging of 7A04 Aluminum Alloy with high strength but low corrosion resistance, innovative gradually cooling three-step aging heat treatment process were designed, conventional mechanical properties and corrosion resistance of 7A04 aluminum after three kinds of aging treatments was studied through microstructure. The results show that compared with the traditional peak aging process, two gradually cooling three-step aging process is to improve materials tensile strength, plastic and impact toughness in different degrees. Meanwhile corrosion resistance of materials has improved significantly. And extension of low temperature aging time is conducive to the further improvement of strength.

CMW 100

Alloy Digest ◽  
2000 ◽  
Vol 49 (10) ◽  
Keyword(s):  
Thermal Conductivity ◽  
Heat Treatment ◽  
Copper Alloy ◽  
High Strength ◽  
Heat Treating ◽  
Age Hardening ◽  
High Tensile Strength ◽  
Electrical Components ◽  
Flash Welding ◽  
Hardening Heat Treatment

Abstract CMW 100 is a copper alloy that combines high tensile strength with high electrical and thermal conductivity. It responds to age-hardening heat treatment. It is used for flash welding dies, springs, electrical components, high-strength backing material for brazed assemblies, and wire guides. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as fatigue. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: CU-29. Producer or source: CMW Inc. Originally published as Mallory 100, August 1955, revised October 2000.

CONFLEX 720

Alloy Digest ◽  
1964 ◽  
Vol 13 (7) ◽  
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Physical Properties ◽  
Surface Treatment ◽  
Nickel Alloy ◽  
High Strength ◽  
Heat Treating ◽  
Age Hardening ◽  
Copper Manganese ◽  
Hardening Heat Treatment

Abstract CONFLEX 720 is a copper-manganese-nickel alloy that responds to an age-hardening heat treatment for high strength and corrosion resistance. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as heat treating, machining, joining, and surface treatment. Filing Code: Cu-143. Producer or source: Metals & Controls Inc..

UNS A97075

Alloy Digest ◽  
1986 ◽  
Vol 35 (7) ◽  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Aluminum Alloy ◽  
High Strength ◽  
Heat Treating ◽  
Good Resistance ◽  
Temperature Performance ◽  
Structural Applications ◽  
Structural Parts ◽  
Very High

Abstract UNS No. A97075 is a wrought precipitation-hardenable aluminum alloy. It has excellent mechanical properties, workability and response to heat treatment and refrigeration. Its typical uses comprise aircraft structural parts and other highly stressed structural applications where very high strength and good resistance to corrosion are required. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength as well as fatigue. It also includes information on low temperature performance as well as forming, heat treating, and machining. Filing Code: Al-269. Producer or source: Various aluminum companies.

ALUMINUM A356

Alloy Digest ◽  
1969 ◽  
Vol 18 (11) ◽  
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
High Strength ◽  
Heat Treating ◽  
Age Hardening ◽  
Casting Alloy ◽  
Permanent Mold ◽  
Aluminum Company ◽  
Mold Casting ◽  
Hardening Heat Treatment

Abstract Aluminum A356 is a sand and permanent mold casting alloy that responds to an age-hardening heat treatment. It is recommended for aircraft and missile components where high strength and corrosion resistance are required. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive and shear strength as well as fatigue. It also includes information on heat treating, machining, and joining. Filing Code: Al-192. Producer or source: Aluminum Company of America.

scholarly journals Development of Precipitation Hardening Parameters for High Strength Alloy AA 7068

Materials ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 918
Author(s):  
Julia Osten ◽  
Benjamin Milkereit ◽  
Michael Reich ◽  
Bin Yang ◽  
Armin Springer ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Cooling Rate ◽  
Maximum Yield ◽  
High Strength ◽  
Tensile Tests ◽  
Age Hardening ◽  
Scanning Calorimetry ◽  
Cooling Rates ◽  
Critical Cooling Rate ◽  
Kinetics Of

The mechanical properties after age hardening heat treatment and the kinetics of related phase transformations of high strength AlZnMgCu alloy AA 7068 were investigated. The experimental work includes differential scanning calorimetry (DSC), differential fast scanning calorimetry (DFSC), sophisticated differential dilatometry (DIL), scanning electron microscopy (SEM), as well as hardness and tensile tests. For the kinetic analysis of quench induced precipitation by dilatometry new metrological methods and evaluation procedures were established. Using DSC, dissolution behaviour during heating to solution annealing temperature was investigated. These experiments allowed for identification of the appropriate temperature and duration for the solution heat treatment. Continuous cooling experiments in DSC, DFSC, and DIL determined the kinetics of quench induced precipitation. DSC and DIL revealed several overlapping precipitation reactions. The critical cooling rate for a complete supersaturation of the solid solution has been identified to be 600 to 800 K/s. At slightly subcritical cooling rates quench induced precipitation results in a direct hardening effect resulting in a technological critical cooling rate of about 100 K/s, i.e., the hardness after ageing reaches a saturation level for cooling rates faster than 100 K/s. Maximum yield strength of above 600 MPa and tensile strength of up to 650 MPa were attained.

Processing of high strength Mg–9Gd–3Nd–1Sn–1Zn–0.6Zr alloy by hot rolling and subsequent aging

2020 ◽  
Vol 10 (7) ◽  
pp. 1020-1031
Author(s):  
Zehua Yan ◽  
Yandong Yu ◽  
Yanchao Sang ◽  
Yiming Yao ◽  
Jiahao Qian
Keyword(s):  
Grain Boundary ◽  
Aging Time ◽  
Hot Rolling ◽  
Aging Treatment ◽  
High Strength ◽  
Subsequent Aging ◽  
Free Zone ◽  
Treatment Conditions ◽  
Peak Aging ◽  
Equilibrium Phases

Magnesium alloy plates can be strengthened by rolling, however, it is easy to crack or even break when the reduction of Mg–RE alloys is too large. Herein, the strengthening mechanical of the Mg–9Gd–3Nd–1Sn–1Zn– 0.6Zr alloy under different treatment conditions were investigated after hot-rolling to 80% reduction in thickness (0.8 mm) by multi-step methods. Furthermore, the rolled alloy by aging strengthening are explored. The results show that the hot-rolled alloy with 80% reduction are basically composed of dynamically recrystallized grains with the size of about 60 m, improving the mechanical properties significantly. The precipitates within grains undergo SSSS→ β″ → β′ phase transformation with the aging treatment up to 200 °C. Fine β″ precipitates were found in the grains of the rolled alloy under aged time (2 h), while β″ precipitates changed into β′ phase when the aging time was extended to 32 h. The base phase which is perpendicular to phase was precipitated in the alloy in longer aging time (96 h). In addition, the thickness of precipitates and precipitation-free zone (PFZ) at the grain boundary gradually increased as the time went on. Meanwhile, the discontinuous equilibrium phases at the grain boundary are gradually become continuous. The ultimate tensile strength and hardness were reached to 431.14 MPa, 105.9 HV at peak-aging, in addition, the elongation is reached to 3.11%, respectively. The formation of crack sources is due to the stress concentration between the brittle PFZ and the magnesium matrix, which leads to the decrease of ductility.

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