Abstract: Refractory metal oxide particles are dispersed in an aluminum melt which is then cast to form a dispersion hardened aluminum alloy composition. A master mix of carrier metal particles surrounding individual oxide particles is pressed into a billet. The billet is dissolved in the melt in the presence of a wetting metal.

Abstract: This invention relates to a manufacturing process for plate or forging (bar, stamp work or the like) of ferrite-austenite two-phase stainless steel, containing C at 0.03% or below, Si at 2.0% or below, Mn at 2.0% or below, Cr at 25 to 35%, Ni at 6 to 15%, N at 0.35% or below, and Fe and inevitable impurity for the remainder with or without adding B at 0.001 to 0.030% with the following nickel balance value specified at -3 to -9 and comprising an average crystal grain size at 0.015 mm or below from heating an ingot of the above mentioned ferrite-austenite two-phase stainless steel at 1,200.degree. C. or below and keeping a forging ratio by hot working at 5 or over.Ni balance value=Ni %+0.5 Mn %+30.times.(C+N) %-1.1(Cr %+1.5 Si %)+8.

Abstract: A method for improving the current confinement capacity of a double heterojunction laser by using a high energy implantation of oxygen in the regions of an injection laser surrounding the active region of such laser so as to make such regions semi-insulating.