الفهرس 
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Abstract
Semisolid metal processing (SSMP) is a technology that involves the
formation of metal alloys between solidus and liquids temperatures. For
the procedure to operate successfully, the microstructure of the starting
material must consist of non-dendritic globular morphology for the solid
phase in liquid matrix. Thus the process of SSMP relies on the thixotropic
behaviour of alloys with a spheroidal rather than a dendritic microstructure
in semisolid state.
Currently, this process is industrially successful, generating a variety
of products with high quality parts in various industrial sectors. This
technology promises some advantages over conventional metal forming
technologies. Aluminium alloys are among the most prominent and wellknown
materials used in the mechanical construction and automotive
industries.
This investigation is focusing on the study of the significance of the
cooling slope (CS) casting process parameters, that are, pouring
temperature, cooling length, and slope angle on the characteristics of
AA7075 high strength wrought aluminium alloy microstructure. The
cooling slope casting is the simplest and cheapest technique for producing
feedstock materials with non-dendritic microstructure.
The AA7075 wrought Al alloy has many good prosperities such as
high strength, high hardness, and light mass. It is widely used in aerospace
and automotive field. Statistical analysis of data is performed to explore
the effect of the process parameters on the microstructure of the AA7075
wrought Al alloy. It was found that there is an optimum condition for the
studying process parameters that provides the best morphology of the
microstructure and the maximum degree of uniformity. The results were
verified by empirical formulas that emphases the calculated results. The
optimum values of pouring temperature, cooling length and tilt angle were
VII
found to be 650 °C, 350 mm and 45°, respectively. The pouring
temperature has highest statistical significance on the results. The
correlation coefficients of the developed regression models for the average
grain size, average shape factor, and aspect ratio are 0.997, 0.960, and
0.983 respectively, which confirms the effectiveness of the developed
models.
VIII
ContentsSemisolid metal processing (SSMP) is a technology that involves the
formation of metal alloys between solidus and liquids temperatures. For
the procedure to operate successfully, the microstructure of the starting
material must consist of non-dendritic globular morphology for the solid
phase in liquid matrix. Thus the process of SSMP relies on the thixotropic
behaviour of alloys with a spheroidal rather than a dendritic microstructure
in semisolid state.
Currently, this process is industrially successful, generating a variety
of products with high quality parts in various industrial sectors. This
technology promises some advantages over conventional metal forming
technologies. Aluminium alloys are among the most prominent and wellknown
materials used in the mechanical construction and automotive
industries.
This investigation is focusing on the study of the significance of the
cooling slope (CS) casting process parameters, that are, pouring
temperature, cooling length, and slope angle on the characteristics of
AA7075 high strength wrought aluminium alloy microstructure. The
cooling slope casting is the simplest and cheapest technique for producing
feedstock materials with non-dendritic microstructure.
The AA7075 wrought Al alloy has many good prosperities such as
high strength, high hardness, and light mass. It is widely used in aerospace
and automotive field. Statistical analysis of data is performed to explore
the effect of the process parameters on the microstructure of the AA7075
wrought Al alloy. It was found that there is an optimum condition for the
studying process parameters that provides the best morphology of the
microstructure and the maximum degree of uniformity. The results were
verified by empirical formulas that emphases the calculated results. The
optimum values of pouring temperature, cooling length and tilt angle were
VII
found to be 650 °C, 350 mm and 45°, respectively. The pouring
temperature has highest statistical significance on the results. The
correlation coefficients of the developed regression models for the average
grain size, average shape factor, and aspect ratio are 0.997, 0.960, and
0.983 respectively, which confirms the effectiveness of the developed
models.
VIII
ContentsSemisolid metal processing (SSMP) is a technology that involves the
formation of metal alloys between solidus and liquids temperatures. For
the procedure to operate successfully, the microstructure of the starting
material must consist of non-dendritic globular morphology for the solid
phase in liquid matrix. Thus the process of SSMP relies on the thixotropic
behaviour of alloys with a spheroidal rather than a dendritic microstructure
in semisolid state.
Currently, this process is industrially successful, generating a variety
of products with high quality parts in various industrial sectors. This
technology promises some advantages over conventional metal forming
technologies. Aluminium alloys are among the most prominent and wellknown
materials used in the mechanical construction and automotive
industries.
This investigation is focusing on the study of the significance of the
cooling slope (CS) casting process parameters, that are, pouring
temperature, cooling length, and slope angle on the characteristics of
AA7075 high strength wrought aluminium alloy microstructure. The
cooling slope casting is the simplest and cheapest technique for producing
feedstock materials with non-dendritic microstructure.
The AA7075 wrought Al alloy has many good prosperities such as
high strength, high hardness, and light mass. It is widely used in aerospace
and automotive field. Statistical analysis of data is performed to explore
the effect of the process parameters on the microstructure of the AA7075
wrought Al alloy. It was found that there is an optimum condition for the
studying process parameters that provides the best morphology of the
microstructure and the maximum degree of uniformity. The results were
verified by empirical formulas that emphases the calculated results. The
optimum values of pouring temperature, cooling length and tilt angle were
VII
found to be 650 °C, 350 mm and 45°, respectively. The pouring
temperature has highest statistical significance on the results. The
correlation coefficients of the developed regression models for the average
grain size, average shape factor, and aspect ratio are 0.997, 0.960, and
0.983 respectively, which confirms the effectiveness of the developed
models.
VIII
ContentsSemisolid metal processing (SSMP) is a technology that involves the
formation of metal alloys between solidus and liquids temperatures. For
the procedure to operate successfully, the microstructure of the starting
material must consist of non-dendritic globular morphology for the solid
phase in liquid matrix. Thus the process of SSMP relies on the thixotropic
behaviour of alloys with a spheroidal rather than a dendritic microstructure
in semisolid state.
Currently, this process is industrially successful, generating a variety
of products with high quality parts in various industrial sectors. This
technology promises some advantages over conventional metal forming
technologies. Aluminium alloys are among the most prominent and wellknown
materials used in the mechanical construction and automotive
industries.
This investigation is focusing on the study of the significance of the
cooling slope (CS) casting process parameters, that are, pouring
temperature, cooling length, and slope angle on the characteristics of
AA7075 high strength wrought aluminium alloy microstructure. The
cooling slope casting is the simplest and cheapest technique for producing
feedstock materials with non-dendritic microstructure.
The AA7075 wrought Al alloy has many good prosperities such as
high strength, high hardness, and light mass. It is widely used in aerospace
and automotive field. Statistical analysis of data is performed to explore
the effect of the process parameters on the microstructure of the AA7075
wrought Al alloy. It was found that there is an optimum condition for the
studying process parameters that provides the best morphology of the
microstructure and the maximum degree of uniformity. The results were
verified by empirical formulas that emphases the calculated results. The
optimum values of pouring temperature, cooling length and tilt angle were
VII
found to be 650 °C, 350 mm and 45°, respectively. The pouring
temperature has highest statistical significance on the results. The
correlation coefficients of the developed regression models for the average
grain size, average shape factor, and aspect ratio are 0.997, 0.960, and
0.983 respectively, which confirms the effectiveness of the developed
models.
VIII
ContentsSemisolid metal processing (SSMP) is a technology that involves the
formation of metal alloys between solidus and liquids temperatures. For
the procedure to operate successfully, the microstructure of the starting
material must consist of non-dendritic globular morphology for the solid
phase in liquid matrix. Thus the process of SSMP relies on the thixotropic
behaviour of alloys with a spheroidal rather than a dendritic microstructure
in semisolid state.
Currently, this process is industrially successful, generating a variety
of products with high quality parts in various industrial sectors. This
technology promises some advantages over conventional metal forming
technologies. Aluminium alloys are among the most prominent and wellknown
materials used in the mechanical construction and automotive
industries.
This investigation is focusing on the study of the significance of the
cooling slope (CS) casting process parameters, that are, pouring
temperature, cooling length, and slope angle on the characteristics of
AA7075 high strength wrought aluminium alloy microstructure. The
cooling slope casting is the simplest and cheapest technique for producing
feedstock materials with non-dendritic microstructure.
The AA7075 wrought Al alloy has many good prosperities such as
high strength, high hardness, and light mass. It is widely used in aerospace
and automotive field. Statistical analysis of data is performed to explore
the effect of the process parameters on the microstructure of the AA7075
wrought Al alloy. It was found that there is an optimum condition for the
studying process parameters that provides the best morphology of the
microstructure and the maximum degree of uniformity. The results were
verified by empirical formulas that emphases the calculated results. The
optimum values of pouring temperature, cooling length and tilt angle were
VII
found to be 650 °C, 350 mm and 45°, respectively. The pouring
temperature has highest statistical significance on the results. The
correlation coefficients of the developed regression models for the average
grain size, average shape factor, and aspect ratio are 0.997, 0.960, and
0.983 respectively, which confirms the effectiveness of the developed
models.
VIII
ContentsSemisolid metal processing (SSMP) is a technology that involves the
formation of metal alloys between solidus and liquids temperatures. For
the procedure to operate successfully, the microstructure of the starting
material must consist of non-dendritic globular morphology for the solid
phase in liquid matrix. Thus the process of SSMP relies on the thixotropic
behaviour of alloys with a spheroidal rather than a dendritic microstructure
in semisolid state.
Currently, this process is industrially successful, generating a variety
of products with high quality parts in various industrial sectors. This
technology promises some advantages over conventional metal forming
technologies. Aluminium alloys are among the most prominent and wellknown
materials used in the mechanical construction and automotive
industries.
This investigation is focusing on the study of the significance of the
cooling slope (CS) casting process parameters, that are, pouring
temperature, cooling length, and slope angle on the characteristics of
AA7075 high strength wrought aluminium alloy microstructure. The
cooling slope casting is the simplest and cheapest technique for producing
feedstock materials with non-dendritic microstructure.
The AA7075 wrought Al alloy has many good prosperities such as
high strength, high hardness, and light mass. It is widely used in aerospace
and automotive field. Statistical analysis of data is performed to explore
the effect of the process parameters on the microstructure of the AA7075
wrought Al alloy. It was found that there is an optimum condition for the
studying process parameters that provides the best morphology of the
microstructure and the maximum degree of uniformity. The results were
verified by empirical formulas that emphases the calculated results. The
optimum values of pouring temperature, cooling length and tilt angle were
VII
found to be 650 °C, 350 mm and 45°, respectively. The pouring
temperature has highest statistical significance on the results. The
correlation coefficients of the developed regression models for the average
grain size, average shape factor, and aspect ratio are 0.997, 0.960, and
0.983 respectively, which confirms the effectiveness of the developed
models.