Crystal and magnetic structures of an annealed Mn–V–Al ternary alloy were investigated by powder neutron diffraction. Neutron diffraction measurements confirmed clearly that the Mn–V–Al alloy specimen with approximate composition Mn₂VAl annealed at 1023 K for 48 h has the Heusler (L2₁)-type structure. Our studies on the annealed alloy specimen, Mn_1.88V_1.12Al_1.00, showed that Mn atom occupies preferentially the simple cubic Mn sublattice α(A+C), while V and Alatoms occupy the B and D sublattices, respectively, in the bcc structure composed of four equivalent fcc sublattices A, B, C and D. It was suggested strongly that Mn atom has the magnetic moment (1.5±0.3)μ_B, in the sublattice α and couples antiferromagnetically with V atom which has the magnetic moment 0.9μ_B in the B sublattice.

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Seven Fe–Si binary alloys with different silicon concentrations ranging from 0.10 to 2.84 mass% were immersed in a pure zinc bath in the temperature range between 713 K and 873 K for 600 s. The thickness of the alloy layer and the quantities of iron having reacted with zinc were measured, and the structure of the alloy layer was observed. These observations were compared with those of pure iron to offer information about the effect of silicon in galvanizing. Results obtained are as follows:
(1) The alloy layer consists of a gamma layer existing next to steel, followed by a delta 1 layer under all the conditions studied. The alloy layer formed next to the delta 1 varies with the silicon concentration of the Fe–Si alloy and the immersion temperature, and four areas are seen in the area map depending on the silicon concentration and the immersion temperature.
(2) The reactivity of the Fe–Zn reaction is higher in the region of 0.10 mass%Si and 713 K–733 K, and also in the region of 1–1.15 mass%Si and 773 K–793 K. The former high reactivity is due to the formation of a thicker zeta layer, and the latter is due to the formation of a thicker (delta 1+eta) layer. On the other hand, this reactivity is low in the region of 0.2–0.3 mass%Si, 713 K–793 K, and in the region of 813 K.
(3) The Fe–Zn reaction above 833 K does not depend on the silicon concentration of the Fe–Si alloy.

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Among various kinds of cast iron, ductile cast iron has good ductility and toughness, for the graphite morphology is spheroidal in this iron. It seems that the possibility of strengthening and toughening of the ductile cast iron lies in the modification of the matrix structure by heat treatment and the addition of alloying elements. In the present study, Ni is added to the ductile cast iron, and various matrix structures are obtained by heat treatment. Effects of these treatments on the toughness are examined.
When the Ni added ductile cast iron is transformed isothermally from the (α+γ) eutectoid temperature range after ferritic annealing, the ferrite plus bainite duplex structure is obtained, and this structure shows a good combination of strength and toughness. The most suitable condition for this treatment to give good toughness even at lower temperature is investigated. Then the Ni added duplex structure ductile cast iron is compared with the ferritic cast iron and the austenitic ductile cast iron by the U-notched Charpy test, fracture toughness test, and tensile test. It is shown that the Ni added ductile cast iron with duplex structure exhibits a good combination of high strength, toughness, and fracture toughness.
It is shown, however, that the transition temperature of the Ni added duplex structure slightly increases compared with the one of the usual ferritic structure in the U-notched Charpy test but largely decreases in the unnotched test. This phenomenon may be due to the transformation induced plasticity effect in the retained austenite phase. It is assumed, therefore, that the main part in the improvement of low temperature toughness in the Ni added duplex structure results from the stabilizing effect in the retained austenite phase by the Ni concentration during holding in the (α+γ) range.

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Solid-liquid interface position and its temperature change during rapid solidification of undercooled liquid have been calculated for three different solidification models taking the coupling of heat flow and crystal growth kinetics into consideration.
The condition for the formation of a glassy state of Fe–C and Pd–Si alloys has been given in terms of the critical undercooling the nucleation of solid crystal below which temperature gives rise to the formation of the glassy state.

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