The thermal spike process is studied in Al–Mg₂Si and Al–Cu alloying systems by means of bombardment-induced photon emission techniques and is accordingly estimated the spike temperature, T=3600 K which shows that the temperature mainly depends on the host material, aluminium. An electron promotion mechanism is also suggested to explain the anomalous phenomena observed in the measurement.

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The kinetic behavior of the Heusler(L2₁)-type ordering in the stoichiometric AuAgZn₂ alloy quenched from the CsCl(B2)-type ordered region was studied by X-ray diffraction. The degrees of the B2-type order (S₁) and the L2₁-type order (S_H) and the domain size of the L2₁-type superstructure were measured as a function of annealing time during the isothermal ordering process at 366, 386 and 406 K. The isothermal change of S_H was analyzed by the standard rate equation and the activation energy of the L2₁-type ordering was found to be 46 kJ/mol. The increase of the L2₁-type domain size was proportional to the three-tenth power of the annealing time. The temperature dependence of S₁ and S_H were also studied. S₁ showed a minimum whereas S_H decreased to zero at the critical temperature of the L2₁-type order on heating.

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Kinetic behavior of the Heusler(L2₁)-type ordering in the stoichiometric AuAgZn₂ alloy quenched from the CsCl(B2)-type ordered phase was investigated theoretically by the quasichemical reaction rate equations. Isothermal changes of the degrees of the B2 and the L2₁-type orders, S₁ and S_H respectively, were obtained by taking into account the direct interchanges of atoms between the 1st and the 2nd nearest neighbors. The frequency factors and the potential barriers for the inter-changes of atoms were estimated. The atomic interchanges between the 1st nearest neighbors as well as those between the 2nd nearest were found to play an important role in the kinetics of the L2₁-type ordering.

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The oxidation behavior of Ni–20Cr–3Si alloys containing 0.004, 0.012 and 0.12% cerium was studied for periods up to 200 h in air at 1273 and 1473 K by weight-change measurements, X-ray diffraction, scanning electron microscopy and electron probe microanalysis. The oxides predominantly formed on the alloys were Cr₂O₃ and SiO₂. The surface oxide formed on Ni–20Cr–3Si and Ni–20Cr–3Si alloys containing 0.004 and 0.012% cerium spalled initially at grain boundaries. For the oxidation times longer than 30 h at 1473 K, spalling of the surface oxide of these alloys occurred mainly at the oxide layer/alloy interface. On the other hand, the weight gain and the weight of the spalled oxide of Ni–20Cr–3Si alloy with 0.12% cerium markedly decreased compared with those of the other alloys.

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The vapor species at about 1170 K over molten S–Se mixture at about 720 K have been measured by mass spectrometry with a double-oven effusion cell and a quadrupole mass spectrometer. The vapor phase at high temperature is mainly composed of S₂(g), Se₂(g) and SSe(g), and the components are in the state of equilibrium. The equilibrium constant K_SSe²=P_SSe²⁄(P_S2×P_Se2) at 1173 K is estimated to be 0.24.

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The composition of CdS_1−xSe_x was controlled by using a reservoir containing the molten S–Se mixture with an accuracy of ±2 at% in the composition range 0.5<x<1.0 and of ±4 at% in 0<x<0.5. Homogeneous crystal was grown through the vapor phase transport using a similar reservoir. The activities of CdS and CdSe in a quasi-binary compound CdS_1−xSe_x was known to deviate slightly to the positive side from the relation of Raoult’s law.

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The effects of annealing on the mechanical properties of Cu–Ni–Zn alloy single crystals with the compositions Cu_(1−2x)Ni_xZn_x and Cu_(0.75−x)Ni_xZn_0.25 (in at%) were studied. The annealing temperature was 573 K.
Results obtained are as follows.
(1) In the group 1 alloys (Cu–5Ni–5Zn, Cu–10Ni–10Zn and Cu–15Ni–15Zn) the annealing effects are not significant and CRSS (critical resolved shear stress) changes with the deformation temperature similarly to the quenched specimens.
(2) In the group 2 alloys (Cu–20Ni–20Zn and Cu–25Ni–25Zn) CRSS increases with the annealing time below 573 K and above it CRSS decreases steeply to the level of quenched specimens.
(3) In the group 3 alloys (Cu–5Ni–25Zn and Cu–15Ni–25Zn) CRSS increases by annealing below 573 K (Cu–15Ni–25Zn) and it has a peak at about 850 K.
(4) The transmission electron micrographs of annealed specimens of the group 2 alloys indicate that they deform by the movement of superlattice dislocations below 573 K. The separation of them has a tendency to increase with the deformation temperature and above 573 K dislocations move as unit ones, because the separation of superlattice ones becomes too large to move as a pair.

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The effects of applied stress on the mean P Auger peak ratio (P-APR) on the intergranular fracture surface of Cr–Mo steel specimens, stressed at less than 50 MPa and aged at 773 K for times up to 100 h, have been studied. The percentage experimental error in the mean P-APR on any given fracture surface was ±2.5% at most when AES measurements were iterated at about 20 different points on each fracture surface under the same analytical condition. Some effect of applied stress on the mean P-APR was found to exist beyond this experimental error. Such an applied stress effect tended to disappear at longer aging times in the smooth type stressed specimens, while it remained even at longer aging times in the notched type of stressed specimens. These effects of applied stress on the mean P-APR were inexplicable in terms of the effect of applied stress on P-bulk diffusivity alone.

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