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Cu-1.9% Be-0.2% Co alloy has excellent mechanical properties such as tensile strength, hardness and fatigue strength(spring characteristics), and is widely used for spring applications. In the present study, heat-treating conditions were investigated in relation to mechanical properties and the micro-structure of the aged alloy. Heat-treating conditions for specimens of 35% final cold-reduction, namely, aging for 2 hours at 330℃ after solution anneal of 0.8㎜ thick specimens for 15 minutes at 800℃ resulted in optimum mechanical properties of 136 ㎏/㎟ tensile strength, 440 micro-Vickers hardness, 2% elongation and 85 ㎏/㎟ fatigue strength. The aging sequence of the alloy established by thin-foil transmission electron microscopy is α→ G.P. zones→γ¹→γ in within grain and α→γ at grain boundaries.

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In order to examine the effects attendant upon varing conditions of glossy ground coat as well as upon the type of carbon contained in the base metal in manufacturing the ceramic coating on cast iron. I have measured the adherence of the wet-process cast iron enamels and the resistance of the thermal shocking, observed the blistering phenomena and surveyed the base with a microscope. This study showed that the ground coat played a main role more in forbidding the blistering than increasing the adherence between the base metal and the cover coat and that the adherence was affected strongly by the composition of the base metal, especially by the ratio of combined carbon and free carbon.

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Because of difficulty to earn good foundry coke, anthracite has been used in the cupola as fuel. Since anthracite has different properties from coke such as low calories, high ash content, softness and so on, cupola had been modified its dimension: lower effective height, high tuyere ratio, high tuyere angle, higher blast pressure and so on. In this paper, the heat balance was calculated by practical operation data, and the results were compared with the heat balance of the regular cupola as follows: 1) With approximately same blast temperature, heat supply by the hot blast in the cupola was 11.50% from total heat supply while regular cupola^(2)) supplied 5.69%. 2) Oxidation heat value by Mn and Fe was appoximately same but in case of Si, oxidation heat value had 0.28% while regular cupola^(2)) had 2.68%. 3) Heat value by the melt had 15.86% in case of mixed fuel while regular cupola^(2)) had 19.66%. 4) Decomposition heat loss by the limestone had 1.78% in case of mixed fuel while regular cupola^(2)) had 0.79%. 5) Heat content in refractory lining, heat emission, formation heat of slag and so on, were 33.53% while regular cupola^(2)) was 24.82%. 6) Combustion heat value by the CO gas had 35.41% while regular cupola had 42.34%. 7) Heat loss percentage by slagging had 4.23% while regular cupola^(2)) had 1.78%.

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The electrolytic apparatus was so made as a barrier was immersed in the shallow pool of Bi-amalgam without reaching the cell bottom. Therefore, the Bi-amalgam was permitted to pass freely, but the supernatant solution was not to. The amalgam, agitated with two stirrers, acted as cathode on one side and as anode on the other of the cell. The electrolytes consisting of Bi(ClO₄)₃ and HClO₄ was used as the refining solution. The recommendable cathode C.D. was 5A-15A/d㎡ and the current efficiency was 100%, The amalgam refining by using 98% Bi as anode resulted in obtaining ≥5-9s.

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The optimum condition for recovering titanium from Korean ilmenite by chlorination process was studied as a function of particle size of ilmenite and charcoal, ratio of charcoal to ilmenite, size of briquette, chlorine flow rate, chlorinating temperature and chlorinating time. It was found that more than 99 percent of titanium was chlorinated when 6-8 mesh briquette made from 1 part of -200 mesh ilmenite and 0.6 part of 100-200 mesh charcoal, was decomposed with chlorine of 750 ㏄./min. at 800℃ for 40 minutes.

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