Special attention has been given in this study to measure the strain-time characteristics of samples in tertiary creep. Tertiary creep is signified by a continuous increase of strain rate. An interesting feature of this strain rate increase was found; The strain rate ata certain time in tertiary creep is inversely proportional to the time up to final failure.
A constitutive equation has been proposed based on the experimental results of creep.The simulation was carried out numerically and the calculated results were compared with the experimentally obtained stress-strain curves.The calculated ones well coincide with theexperimental. It should be emphasized that the proposed constitutive equation can be applied to not only pre-failure region but also post-failure region to some extent.

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Fatigue on component wire in steel wire ropes under tension and superposing alternating bending has been studied.This paper describes the result of the fatigue test of a steel wirewhich bears a natural curl, and discusses the stress on component wire considering the curvature. Result of observation of the fracture surface on specimen is also discussed. The similarity between the bending of single wire and the equivalent bending of a particular component wire in a 7×7 wire rope is investigated.

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In order to improve the refractoriness of low grade Amakusa pottery clay which is composedof quartz, feldspar (albite) and clay minerals, we have investigated the possibility of the application of flotation process for the removal of feldspar from the clay. The resultsobtained from batch flotation tests and particle size analysis on the flotation products are summarized as follows:
1) In the first stage, clay minerals are separated from quartz and albite by clay flotation in acid circuit. In the second stage, albite in non-float of the clay flotation is separated from quartz in the presence of hydrofluoric acid by feldspar flotatio Ann.d pottercy layp roducti n whicha lbities r emovedt o some extenct an be producedb y mixingt Hef loaotf clay flotation with non-float of feldspar flotation. Especially, it was effective to add the small amount of COAC (Coco amine hydrochloride) as collector stepwise.
2) Following optimum flotation conditions were determined. i) Clay flotation; pulp density 10%, flotation pH 2.7 (adjusted with H₂SO₄), COACas collector 50×4g/t (a 50g/t of COAC is stepwise added four times.), pine oil as frother 170g/t, ii) Feldspar flotation; pulp density 10%, flotation pH 2.1 (HF 20kg/t), COAC 200×4g/t, pine oil 170g/t.
3) In the early stage of clay flotation, coarse particles tend to float, however, in that of feldspar flotation, fine particles tend to float.
4) In clay flotation, quartz and albite of fine particles (-5μm) have a tendency to be incorporated into float in comparison with those of coarse particles. But in feldspar flotation, quartz of coarse particles (+10μm) have a tendency to be incorporated into floatin comparison with those of fine particles.
5) The refractoriness of pottery clay product by two stage flotation was improved from SK 15 to SK 18.

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Distribution ratios of As and Sb between the melts of Na₂CO₃-Na₂O-SiO₂ and metallic copper were measured at 1250°C. The results are as follows:
1) Distributions of As and Sb between sodium carbonate salt or Cu₂O-base slag and metallic copper were determined under coexistence of these three melts.
2) Distributions of As and Sb between sodium silicate slag or Cu₂O-base slagand metallic copper were determined under coexistence of these three melts.
3) Dependence of distribution ratios on soda-ratio and oxygen partial pressure was determined. The pentavalent oxide of As is predominant species in basic slags at high oxygen partial pressure. It is easy to eliminate As rather than Sb from crude copper by use of basic slag.
4) Distribution ratios of As, Sb and Cu at po₂=10^-8 atm increasewith Na₂X and reach the maximum values at 0.7 sodaradio. Above 0.7 soda-ratiothe distribution ratios decrease with increase in Na₂X (X=O, CO₃) dueto the existence of carbonate.

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The behaviour of germanium was studied under the conditions similar to those of roasting, purification and electrowinning stages of electrolytic production of zinc.
Some principal results of the experiments are as follows:
(1) In the course of roasting of GeO₂-ZnSmixture at 900°C in the stream of air, GeO₂ reacted with ZnO to form Zn2GeO₄.
(2) Coprecipitation of germanium with Fe (OH) 3 was observed to proceed most effectively at pH of about 9. Higher molar ratio of Fe³⁺ to Ge andlower temperature reduced the concentration of the germanium remaining in solution.
(3) Removal of germanium from ZnSO₄ solution ([Zn] =150g/l) at pH 4.0 and 4.5 usingzinc powder was remarkably enhanced by the presence of Cu²⁺ in the solution. The favourable condition for germanium elimination was accompanied with an increase in dissolution rate of zinc powder.
(4) In electrowinning of zinc, germanium in electrolyte caused drastic increase in hydrogen evolution and redissolution of zinc deposit. This noxiouseffect was detected at such a low concentration of germanium as 0.01mg/l.

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