Amorphous metallic foam
نویسندگان
چکیده
The bulk glass forming alloy Pd43Ni10Cu27P20 is processed into a low-density amorphous metallic foam. Pd43Ni10Cu27P20 is mixed with hydrated B2O3 , which releases gas at elevated temperature and/or low pressure. Very homogeneous foams are achieved due to the high viscosity of the alloy even at its liquidus temperature. By processing at the liquidus temperature and decreasing the pressure to 10 mbar, well-distributed bubbles expand to foam the material. Foam densities as low as 1.4310 kg/m were obtained, corresponding to a bubble volume fraction of 84%. The bubble diameter ranges between 2310 and 1310 m. Thermal analysis by differential scanning calorimetry confirms the amorphous nature of the foam. Furthermore, it reveals that the foam’s thermal stability is comparable to the bulk material. © 2003 American Institute of Physics. @DOI: 10.1063/1.1537514#
منابع مشابه
Synthesis method for amorphous metallic foam
A synthesis method for the production of amorphous metallic foam is introduced. This method utilizes the thermodynamic stability and thermoplastic formability of the supercooled liquid state to produce low-density amorphous metallic foams in dimensions that are not limited to the critical casting thickness. The method consists of three stages: the prefoaming stage, in which a large number of sm...
متن کاملAmorphous Mg-based metal foams with ductile hollow spheres
To date, high compressive ductility and energy absorption have been achieved in amorphous metal foams based on high-toughness Pdand Zr-based metallic glasses and are known to result from two extrinsic toughening mechanisms: bending of struts and shear band arrest by pores. We study here a syntactic amorphous metallic foam produced by infiltration of a bed of hollow crystalline iron spheres with...
متن کاملAcoustic emissions analysis of damage in amorphous and crystalline metal foams
Acoustic emission methods are used to investigate the nature and evolution of microfracture damage during uniaxial compression of ductile amorphous and brittle crystalline metal foams made from a commercial Zr-based bulk metallic glass, and to compare this behavior against that of aluminum-based foam of similar structure. For the amorphous foam, acoustic activity reveals evolution of the damage...
متن کاملAmorphous metal foams
As recently demonstrated, amorphous metal foams are highly ductile in compression, and thus offer attractive compromises in mechanical and physical properties between crystalline metallic and ceramic foams. Challenges associated with fabrication of amorphous metal foams are critically assessed in the context of current and future processing methods, and conclusions are drawn regarding the prope...
متن کاملOxidation Behavior of a Pd43Cu27Ni10P20 Bulk Metallic Glass and Foam in Dry Air
The oxidation behavior of both Pd43Cu27Ni10P20 bulk metallic glass (Pd4-BMG) and its amorphous foam containing 45 pct porosity (Pd4-AF) was investigated over the temperature range of 343 K (70 C) to 623 K (350 C) in dry air. The results showed that virtually no oxidation occurred in the Pd4-BMG at T< 523 K (250 C), revealing the alloy’s favorable oxidation resistance in this temperature range. ...
متن کامل