Accession Number:

ADA621699

Title:

Microstructures and Mechanical Responses of Powder Metallurgy Noncombustive Magnesium Extruded Alloy by Rapid Solidification Process in Mass Production

Descriptive Note:

Final rept. Dec 2008-May 2010

Corporate Author:

OSAKA UNIV IBARAKI (JAPAN)

Report Date:

2010-05-01

Pagination or Media Count:

26.0

Abstract:

Spinning water atomization process SWAP, one of the rapid solidification processes, promised to produce coarse noncombustible magnesium alloy powder 1 4 mm long and have fine alpha-Mg grains and Al2Ca intermetallic compounds. SWAP had economical and safe benefits in producing coarse Mg alloy powders with very fine microstructures in the mass production process due to its extreme high solidification rate compared to the conventional atomization process. AMX602 Mg-6Al-0.5Mn-2Ca powders were compacted at room temperature. Their green compacts, with a relative density of about 85, were heated at 573-673 K for 300 s in Ar gas atmosphere and immediately consolidated by hot extrusion. Microstructure observation and evaluation of mechanical properties of the extruded AMX602 alloys were carried out. The uniform and fine microstructures, with grains 0.45-0.8 microns via dynamic recrystallization during hot extrusion, were observed and much smaller in comparison to the extruded AMX602 alloy fabricated from cast ingot. The extremely fine intermetallic compounds, 200-500 nm in diameter, were uniformly distributed in the matrix of powder metallurgy extruded alloys. These microstructures caused excellent mechanical properties of the wrought alloys. For example, in the case of AMX602 alloys extruded at 573 K, tensile strength of 447 MPa, yield stress of 425 MPa, and 9.6 elongation were obtained.

Subject Categories:

  • Properties of Metals and Alloys
  • Fabrication Metallurgy
  • Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE