Effect of T6 heat treatment on corrosion resistance and mechanical properties of AM50 magnesium alloy

The corrosion behavior of as-cast AZ91C magnesium alloy was studied by performing friction stir processing (FSP) and FSP followed by solution annealing and then aging. Phase analysis, microstructural characterization, potentiodynamic polarization test and immersion tests were carried out to relate the corrosion behavior to the samples microstructure. The microstructural observations revealed the breakage and dissolution of coarse dendritic microstructure as well as the coarse secondary [Formula: see text]-Mg[Formula: see text]Al[Formula: see text] phase which resulted in a homogenized and fine grained microstructure (15[Formula: see text][Formula: see text]m). T6 heat treatment resulted in an excessive growth and dispersion of the secondary phases in the microstructure of FSP zone. The potentiodynamic polarization and immersion tests proved a significant effect of both FSP and FSP followed by T6 on increasing the corrosion resistance of the cast AZ91C magnesium alloy. Improve in corrosion resistance after FSP was attributed to grain refinement and elimination of segregations and casting defects which makes more adhesive passive layer. Increase in volume fraction of precipitations after T6 heat treatment is determined to be the main factor which stabilizes the passive layer at different polarization values and is considered to be responsible for increasing the corrosion resistance.

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Effect of Heat Treatment on Microstructure and Mechanical Properties of Semi-Solid Formed Magnesium Alloy AZ91D

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.346 ◽

2010 ◽

Vol 148-149 ◽

pp. 346-352

Author(s):

Dong Nan Li ◽

Wen Zhe Chen ◽

Jun Tian

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

Magnesium Alloy ◽

Die Casting ◽

Primary Phase ◽

T6 Heat Treatment ◽

Microstructure And Mechanical Properties ◽

Alloy Az91d ◽

Semi Solid

The semi-solid slurry of AZ91D magnesium alloy was prepared by twin-screw stirring mixer, the microstructure and mechanical properties of semi-solid formed magnesium alloy AZ91D produced by rheo-diecasting and conventional liquid die casting were investigated, respectively. The strengthen mechanism of the semi-solid formed magnesium alloy after heat treatment was analysed by EDS. The results show that the mechanical properties of semi-solid formed magnesium alloy can be enhanced markedly by T4 and T6 heat treatment, owing to decrease of the porosity and less segregation in casting, brittle eutectic compounds dissolves gradually into α-Mg matrix, and the primary phase α-Mg decomposes in the course of heat treatment. In as-cast state, the tensile strength, elongation and hardness of semi-solid formed magnesium alloy AZ91D are 222MPa, 2.3% and 74 HBS, respectively. In T4 heat treatment state, the tensile strength and elongation are increased by 13% and 210%, and in T6 heat treatment state, the tensile strength and hardness are increased by 11% and 16%. The mechanical properties of castings formed by conventional liquid die casting are deteriorated distinctly after T6 heat treatment due to its porosity and crack defects.

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Study on Microstructure and Mechanical Properties of Mg9AlZnGdY Magnesium Alloy after T6 in Lost Foam Casting

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.291-294.565 ◽

2011 ◽

Vol 291-294 ◽

pp. 565-568

Author(s):

Zhong Zhao ◽

Qiang Luo ◽

Zi Tian Fan

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

High Temperature ◽

Magnesium Alloy ◽

Grain Boundary ◽

Lost Foam Casting ◽

High Temperature Strength ◽

T6 Heat Treatment ◽

Lost Foam

The microstructures and mechanical properties of Mg9AlZnGdY alloy after T6 heat treatment in lost foam casting (LFC) are compared with that of AZ91D magnesium alloy. The results show that the microstructures of Mg9AlZnGdY alloy after T6 heat treatment consist of the α-Mg solid solution, β-Mg17Al12 precipitation phase, a small amount of rod Al2Y and block Al2Gd phases, which are distributed over grain boundaries of the α-Mg phase. The thermal stability of Al2Y and Al2Gd phases offers the pinning effect on the grain boundary under high temperature, and therefore, the grain boundary sliding is eliminated and the high-temperature strength is increased. After the T6 heat treatment, the tensile strength of Mg9AlZnGdY alloy was 235MPa at room temperature, and 156MPa at 200°C. Compared with that of AZ91D alloy, the tensile strength was increased by 19.3% and 38.1% respectively.

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ALUMINUM 3004

Alloy Digest ◽

10.31399/asm.ad.al0051 ◽

1974 ◽

Vol 23 (4) ◽

Keyword(s):

Heat Treatment ◽

Corrosion Resistance ◽

Shear Strength ◽

High Temperature ◽

Magnesium Alloy ◽

Cold Working ◽

Heat Treating ◽

Temperature Performance ◽

Good Workability ◽

Manganese Magnesium

Abstract ALUMINUM 3004 is nominally an aluminum-manganese-magnesium alloy which cannot be hardened by heat treatment; however, it can be strain hardened by cold working. It has higher strength than Aluminum 3003 and good workability, weldability and resistance to corrosion. 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 low and high temperature performance, and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Al-51. Producer or source: Various aluminum companies. Originally published June 1957, revised April 1974.

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ALUMINUM 62S

Alloy Digest ◽

10.31399/asm.ad.al0011 ◽

1953 ◽

Vol 2 (12) ◽

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Corrosion Resistance ◽

Salt Water ◽

Heat Treating ◽

Magnesium Silicide ◽

Age Hardening ◽

Aluminum Company ◽

Wrought Aluminum ◽

Hardening Heat Treatment

Abstract ALUMINUM 62S is a magnesium silicide type of wrought aluminum alloy with high resistance to fresh and salt water corrosion. It responds to age hardening heat treatment for high mechanical properties. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Al-11. Producer or source: Aluminum Company of America.

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