Stress change tests during the steady state creep of aluminum alloy 3004 at 300°C

Stress change tests during steady state creep have been used to study the creep behaviour of aluminium alloy 3004 (Al-1.01wt.%Mn-0.97wt.%Mg-0.36wt.%Si-0.39wt.%Fe-0.19wt.%Cu) at 300°C and the results compared with those for binary AlMg alloys made from high purity metals. Similarities in the shape of the primary creep curves, instantaneous strains and work-hardening rates are considered to arise because the viscous glide is rate controlling in both alloy 3004 and binary AlMg alloys. Differences in the stress exponents of steady state creep and the internal (back) stresses are considered to be due to the presence of precipitates in alloy 3004

Synthesis of Ag or Pt Nanoparticles by Hydrolysis of Either Ag2Na or PtNa

Ag and Pt nanoparticles have successfully been synthesized by hydrolysis of either Ag2Na or PtNa at room temperature. The oxidation of sodium in the Pt-Na pellets was much faster than that in the Ag-Na pellets since Pt is a catalyst for H2O formation reaction from hydrogen and oxygen at room temperature. The hydrolysis byproduct, NaOH, has a high solubility and easily is removed. This method offers a simple method of preparing transition metal nanoparticles. The Ag and Pt nanoparticles prepared by this method were crystalline in nature, and spherical in shape with a mean size of around 10 nm