Narrow Results

A misch metal, an alloy of light rare earth elements, was analyzed by a new coupled analytical method, ITP-PIXE(isotachophoresis—Particle Induced X-ray Emission) : The sample solution containing ca.1 mg misch metal was separated and fractionated by the use of a preparative isotacho-phoretic analyzer. The dropwise fractions containing nanomole rare earth elements were analyzed off-line by PIXE. The matrix effect in X-ray measurement was reduced by the isotachophoretic removing of the dominant lanthanoids and preconcentration of the trace elements of interest. Consequently the minor elements, Sm, Gd, Tb, Dy, Ho, Er, Yb and Y could be determined accurately. The most trace element found was Yb (4ppm, 4ng in 1mg sample). The good accuracy of ITP-PIXE method was also demonstrated for several model samples of lanthanoids, where La was the dominant element and the thirteen lanthanoids were the minor elements. The ratio was varied from 500:1 to 50000:1. Even in the case of 50000:1, ca. 10% accuracy was achieved for each minor element except for Sm(23%), Gd(17%) and Yb(18%). The analytical results by ITP-PIXE were compared with those by means of ICP-AES(Inductively Coupled Plasma—Atomic Emission Spectrometry).

In the present works, the change of a rolling texture by La or Mm (Misch metal) addition in high Mg content (>5wt%) Al-Mg alloy was investigated. By Mm addition, B (Brass) orientation {011} 〈112〉 was typically developed with Mg contents and it was accelerated by La, Mm additions. TC (twin copper) orientation {255} 〈511〉 and G (Goss) orientation {110} 〈001〉 orientations closely related mechanical twinning were decreased in intensity and development of coarsen share bend was suppressed by Mm addition in Al-10wt%Mg alloy. And it caused improvement of formability by Mm addition in high Mg content Al-Mg alloy.