Spray Forming of AZ91 Magnesium Alloys with and without Si Addition

ray forming was employed to refine the microstructures of AZ91 and AZ91-3.34wt%Si Mg alloys during solidification by means of rapid solidification generated at atomization and droplet flight stages. The process parameters of spray forming were varied to reduce the porosity level and improve the morphology of the billet preforms. As-spray-formed microstructures were characterized using OM, SEM/EDS, and XRD, which were compared with as-cast microstructures. The significant differences of grains, Mg2Si and Mg17Al12 in morphology and in size between as-spray-fromed and as-cast materials are mainly due to fast cooling and solidification rates of spray forming process. Supersaturated matrix is found in as-spray-formed materials due to rapid solidification generated by spray forming. Overall, spray-formed materials are shown to have four characteristics, which are much finer microstructures, uniformly distributed phases, equiaxed-shaped phases, and supersaturated matrix.

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Spray Forming of AZ91 Magnesium Alloys with and without Si Addition

Materials Science Forum - PRICM-5 ◽

10.4028/0-87849-960-1.2789 ◽

2005 ◽

pp. 2789-2794

Author(s):

C.Y. Chen ◽

Chi Y.A. Tsao

Keyword(s):

Magnesium Alloys ◽

Spray Forming ◽

Az91 Magnesium ◽

Si Addition

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Microstructural Evolution and Mechanical Properties of AZ91 and SiCp/AZ91 Magnesium Alloys upon Rapid Solidification/Powder Metallurgy Followed by Hot Extrusion

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.146-147.734 ◽

2010 ◽

Vol 146-147 ◽

pp. 734-737

Author(s):

Hui Yu ◽

Hua Shun Yu ◽

Zhen Ya Zhang ◽

Guang Hui Min ◽

Cheng Chen

Keyword(s):

Mechanical Properties ◽

Powder Metallurgy ◽

Magnesium Alloys ◽

Rapid Solidification ◽

Microstructural Evolution ◽

Hot Extrusion ◽

Interface Debonding ◽

Porosity Level ◽

Az91 Magnesium ◽

Sic Particulates

In this study, AZ91 and SiC particulates reinforced AZ91 (SiCp/AZ91) magnesium alloys were successfully fabricated using rapid solidification/powder metallurgy technique followed by hot extrusion. Microstructural evolution and mechanical properties of the monolithic AZ91 and SiCp/AZ91 magnesium alloys were evaluated. SiC particulates were well distributed with only few agglomerated particles. The porosity level and microhardness increased as SiCp content increased because the increased surface area of SiCp, harder ceramic phases and SiCp acted obstacles to the motion of dislocations. In addition, an increase in particulate reinforcement content was observed to decrease mechanical properties of the composite compared with the unreinforced counterpart due to increasing agglomerating regions and porosity, brittle interface debonding between matrix and SiCp.

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Effect of Heat Treatment on Tensile Strength and Microstructure of AZ61A Magnesium Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.606.55 ◽

2014 ◽

Vol 606 ◽

pp. 55-59 ◽

Cited By ~ 2

Author(s):

R. Senthil ◽

A. Gnanavelbabu

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Tensile Strength ◽

Magnesium Alloy ◽

Magnesium Alloys ◽

Mg Alloys ◽

Forming Process ◽

Microstructural Parameters ◽

Heat Treated ◽

Mutual Relations

Magnesium alloys are the very progressive materials whereon is due to improve their end-use properties. Especially, wrought Mg alloys attract attention since they have more advantageous mechanical properties than cast Mg alloys. Investigations were carried out the effects of heat treatment on tensile strength and microstructure of AZ61A magnesium alloy. The AZ61A Mg alloy is solution heat treated at the temperature of 6500F (343°C) for various soaking timing such as 120 min, 240 min and 360 minutes and allowed it cool slowly in the furnace itself. Magnesium alloys usually are heat treated either to improve mechanical properties or as means of conditioning for specific fabrication operations. Special attention had been focused on the analysis of mutual relations existing between the deformation conditions, microstructural parameters, grain size and the achieved mechanical properties. The result after the solution heat treatment, showed remarkably improved hardness, tensile strength and yield strength. It would be appropriate for a forming process namely isostatic forming process.

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Development of Rapid Solidification Aluminum Alloy Using the Spray Forming Process

The Proceedings of the Materials and processing conference ◽

10.1299/jsmemp.2004.12.281 ◽

2004 ◽

Vol 2004.12 (0) ◽

pp. 281-282

Author(s):

Nozomu KAWASETSU ◽

Keiichi SHIRAISHI ◽

Yukihiro IWASA ◽

Koichiro IMAKIIRE ◽

Yasuo OHFUKUNE

Keyword(s):

Aluminum Alloy ◽

Rapid Solidification ◽

Spray Forming ◽

Forming Process

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Corrosion Characterization of Magnesium Alloys – The Role of Process Parameters

Materials Science Forum ◽

10.4028/www.scientific.net/msf.783-786.346 ◽

2014 ◽

Vol 783-786 ◽

pp. 346-351

Author(s):

Guy Ben-Hamu

Keyword(s):

Electron Microscopy ◽

Comparative Study ◽

Magnesium Alloys ◽

Corrosion Behavior ◽

Process Parameters ◽

Mg Alloys ◽

Die Cast ◽

Dc Polarization

The present work presents a comparative study of FSW die cast AM50 Mg alloy. The main focus is the effect of the FSW metallurgy on the corrosion behavior of the alloy. AC and DC polarization tests were carried out on the FSW Mg alloys. The microstructure was examined using electron microscopy (SEM).

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AZ80 Mg Alloy Synthesized by Spray Forming and its Extrudability

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.479.27 ◽

2011 ◽

Vol 479 ◽

pp. 27-33

Author(s):

Shih Han Wang ◽

Chi Y.A. Tsao

Keyword(s):

Rapid Solidification ◽

Solidification Process ◽

Extrusion Process ◽

Spray Forming ◽

Mg Alloy ◽

Rapid Solidification Process ◽

Forming Process ◽

Extrusion Speed ◽

Green House Gas ◽

Conventionally Cast

Magnesium materials are gaining an increasing interest especially in transportation industries. The goals are the reduction of fuel and the reduction of the green house gas CO2. To achieve these goals, the weight of vehicles must be reduced. Compared to Al based materials, Mg based materials offer the possibility of saving up to 30% in weight. Unfortunately the latter suffer from poor workability. The workability of AZ91B has been proven to be improved significantly by employing the rapid solidification process, Spray Forming. In this study, the AZ80 Mg alloy was synthesized via Spray Forming process. The microstructures were characterized and compared with conventionally cast materials. The workability of the spray-formed AZ80 Mg alloys was studies via a simple extrusion process. The effects of the extrusion speed and temperature on the workability were investigated.

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Mathematical Simulation of Billet Profile during Spray Forming Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.1961 ◽

2007 ◽

Vol 561-565 ◽

pp. 1961-1966 ◽

Cited By ~ 2

Author(s):

San Bing Ren ◽

Jun Fei Fan ◽

Hai Rong Le ◽

Shun Li Zhao

Keyword(s):

Mathematical Model ◽

Mathematical Simulation ◽

Process Parameters ◽

Rotation Speed ◽

Spray Forming ◽

Forming Process ◽

Simulation And Experiment ◽

Billet Shape ◽

Eccentric Distance

The parameters of atomizer were obtained from the experiment. Based on the obtained parameters, a mathematical model was proposed to simulate the growing profile of billet during spray forming. The model included some process parameters which relate to the shape profile such as nozzle data, eccentric distance, rotation speed, withdraw speed and so on. After being compared with the billet shape of experiment, we got good consistent results between the simulation and experiment, it was found that the results of the simulation is in good consistent with that of the experiment.

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