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The synthesis of Nd-Fe-Co-B by the reduction-diffusion process from neodymium trichloride and its magnetic properties and microstructure have been investigated by x-ray diffraction, scanning electron microscope, and magnetic analysis. According to the thermodynamic data, calcium is capable of reducing neodymium trichloride and then a Nd-Fe-Co-B aHoy is formed by thermal diffusion in the presence of iron, cobalt, and ferro-boron powders at high temperature. The reduction reaction starts at 720 ·C. Thermal diffusion commenced at 800 ·C and forming some Nd 2 Fe ,4 B phase, but the matrix Nd 2 Fe l4 B formed primarily at 860--950 0c.There are three types of phases with different compositions in the sintered Nd-Pe-Co-B RID powders. The oxygen and calcium contents were 0.2 and 0.1 wt. 0/0, respectively. The best yield of Nd-Fe-Co-B powder was up to 98%. The magnetic properties of the sintcred Nd-Fe-Co-B depended on the temperature and time of the reduction-diffusion process. The best magnetic properties obtained were Br = 12.6 kGs, He = 8 kOe, and (BII) m = 36.4 MGOe.

Annealing of cold‐rolled supersaturated Al–1.3 wt% Mn leads to heavy precipitation of fine particles on the as‐deformed microstructure. Depending on the crystallographic orientation of the deformed matrix grains, particles with different morphologies, namely spherical, rhomboidal and plate‐like, have been observed. This variation in morphology could be traced back to differences in local misorientation caused by different dislocation substructures in different matrix orientations. Microstructural investigations and selected‐area diffraction (SAD) analysis in a transmission electron microscopy (TEM) study were employed to characterize the various particles and to determine their orientation relationship to the Al matrix. Independent of the particle morphology, most Mn precipitates were identified as Al6Mn; only occasionally was Al12Mn observed. Upon consideration of the various crystal symmetries, two different orientation relationships were discerned, which can be written as (110)m||(111)p, [001]m||[2¯11]p and (110)m||(111)p, [11¯2]m||[12¯1]p. These orientation relationships are discussed with respect to the existence of several low misfits of lattice spacings and compared to literature data.

A study has been carried out on an Fe--Q.11 % G-1.58% Si-Q.4% Mn-dual phase steel. The dual-phase microstructures and properties are significantly affected by both the intercritical temperature and cooling rate from (ex + y) field. Upon rapid cooling (water or oil quench) from the temperature range 735-820°C, the structure comprises ferrite + martensite. On the other hand, slow cooling (air cooling) from the temperature range 735-820°C produces microstructures containing ferrite + martensite + pearlite/bainite and more favourable mechanical properties as: 0"0.2 = 281-296 MPa, O"UTS = 632-690 MPa, TE = 26-30% and continuous yielding behaviour. MikrogefUge und Eigenschaften eines e-Mn-Si-Dualphasenstahls. Es wurde ein Fe--Q, 11%-G-1 ,58%-Si-Q,4%-Mn-Dualphasenstahl untersucht. Das Dualphasen-MikrogefUge und die Eigenschaften werden durch die interkritische Temperatur und die Abkuhlqeschwindiqkeit aus dem ex-y-Gebiet beeinfluBt. Bei schneller Abkuhlung (mit Wasser oder 01) von 735 bis 820°C besteht das GefUge aus Ferrit und Martensit. Andererseits besteht das GefUge nach langsamer Abkuhlung von 735 bis 820°C aus Ferrit, Martensit und PerlitiBainit mit sehr guten Eigenschaften wie R O • 2 = 281-296 MPa, R m = 632-690 MPa, A = 26-30 % und einer kontinuierlichen Streckgrenze.