Recently, as the production of high grade cast iron has increased, together with the improvement of mechanical properties, the problem of wear resistivity has been taken up. In this investigation, comparison was made on wear resisting properties of deoxidized high grade cast iron with those of other cast irons.
  The results can be summarized as follows:
  In cast iron, graphite carbon acts as lubricant, therefore it is proved its feature in wear resistivity. Deoxidized high grade cast irons have superior properties in wear resistivity by its strong, tough qualities, and graphite carbon (or oil lubricant). This reason is that the pearlitic matrix has strong and tough qualities, and wormy flake graphite or spheroidal graphite being created by the desxidation. Eutectic graphite cast iron does not prove wear resistivity under heavy load.

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  The effect of the amount of ferrite in the matrix of spheroidal graphite cast iron on wear resistance is studied by the sliding wear test with no lubrication in this report, contacting spheroidal graphite cast iron with ordinary cast iron or carbon steel.
  As far as the condition of this experiment, the gist of the results can be summarized as follows:
  1) The effect of ferrite on wear resistability of spheroidal graphite cast iron is great and as the amount of ferrite increases, the resistability becomes poorer.
  2) However, the effect is influenced by the testing condition and in general, it is comparatively small when the contacting pressure is low, but as the pressure becomes higher, it increases rapidly. Also, it becomes remarkable as the frictional velocity becomes slower.
  3) As to the effect on the parent metals as ordinary cast iron or steel in the case of low pressure, the wear of the parent metal increases as the amount of ferrite in the matrix of spheroidal graphite cast iron increases, but contrary to this, the inverse tendency is observed when the pressure becomes greater,
  4) When wear resistability of spheroidal graphite cast iron against ordinary cast iron or steel is compared with that of flaky graphite cast iron, the former is superior than the later and especially, as the contacting pressure becomes higher, the difference in resistability becomes greater. Consequently, it is believed the effect of spheroidization of graphite on the wear resistance of cast iron is extremely great.
  5) The wear of spheroidal graphite cast iron against ordinary cast iron is generally smaller than that of against carbon steel.

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  In our report 2, we described the experimental results and the considerations about the influences of tuyeres upon the combustion of high quality low ash coke in cupopla. In this report, we will inform the results of the identically performed experiments for high ash (16%) low quality coke and for medium ash (8%) high quality coke.
  The gist of the results obtained are as follows:
  1) when the small sized horizontal tuyeres are used for high ash low quality coke, the blast cools the coke which is situated in front of the tuyere, and the combustion becomes ununiform. large sized tuyeres, horizontal or downward inclined, have the same, though a slightly small, tendency. Small sized downward inclined tuyeres have no-cooling effect by the blast, and are most favourable from the view-point of combustion.
  2) In the case of the medium ash high quality coke, coke combustion becomes ununiform by using the small sized tuyeres, both horizontal and down-ward inclined, and the former intensifies the combustion at the far-off point to tuyere, and the later at the adjacent point. large sized tuyeres, both horizontal and iuclined, are preferable from the vew-point of coke combustion.
  3) For low ash high quality coke, it is thought, as informed in Rep. 2, that the size of tuyeres has not so different effects to coke combustion as mentioned above.
  4) From the view-point of the resistance to blast, large sized tuyeres are profitable.

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  Fundamental effects of calcium on the cast iron were studied. To prevent the loss of calcium by oxidation and to know the direct effects of calcium, metal grains of it were added on the iron molten under vacuum and the microstructure and the chemical compositions of the irons cooled and solidified in vacuum-furnace were discussed.
  The results obtained are summarized as follows:
  1) Calcium is considered as a powerful graphitizer.
  2) Graphitizing power of calcium does not introduced by the indirect effect owing to deoxidation, but by the direct effect.
  3) To deposit the spheroidal graphite in low carbon iron by calcium addition, low content of silicon is desirable so long as the graphitization is not prevented.
  4) The more the content of silicon is, the better the kish graphite in high carbon iron spherodize.
  5) Calcium is considered as a powerful inoculant.
  6) Reactions of calcium with the molten iron are fundamentally effective even at low temperature as 1300°C.

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  The major purpose of this study is to obtain the data in connection to clay minerals contained in green sand. These minerals are not only generated in the residual clays formed by decomposition of the parent materials, but also they are transported ane deposited as sediments. Generally, these clay minerals are composed of hydrated halloysite, montmorillonite and kaolinite. But some samples contain sericite of minor quantity. However quantitative relation between these clay minerals is various, we can divied into clases as follows:
  (1) those contain montmorillonite predominantly.
  (2) those contain hydrated halloysite predominantly.
  (3) those contain both minerals in various ratioes.
  Generally speaking, kaolinite is minor accessory mineral. These differences depend on vavious geological factors.

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  There have been many investigations on fluidity of metals and alloys referring to the casting temperature or to the composition of the alloys, but still there has never drawn any final conclusion. The authors have carried out the experimental study on it by applying the electro-magnetic oscillograph, the lamp method apparatus and the microscopic observation to get more approach to the nature of the metal flow, and to find out the factors controlling the flow lengths of metals and alloys. pure alum-inium, aluminium-silicon and aluminium-copper alloys were cast at 750° or 700° to a straight narrow channel of 6×9mm section of green sand mould and the mechanism of the flow is investigated and discussed.
  The results of the present investigation are summarlized as follows:
  1) The variation of the flow length in aluminium-sillcon and aluminium-copper alloy cast in a sand mould is similar to those of the previous investigations, and the minimum value of it is obtained about the composition of the alloy with the maximum solidification range.
  2) The metal is agitated when it is poured in the mould and the velocity of flow fluctuates in the earlier stage when it flows into a narrow straight channal. Then the flowing velocity reduces gradually in alloys of wide solidification range, but it changes rather abruptly in pure metals or in eutectic alloys.
  3) pure aluminium flows above the melting point in an earlier stage, but it keeps running at the melting point in the following stage when it flows into a narrow channel. Then, the front of the running metal is often super-cooled. The solidification begins at the front and the flow stops. while, with the alloys of wide solidification range, the flowing alloys seperate the primary crystals and the residual solution keeps running. The solidification begins at the rear part of the flow; the front part of the mould cavity of the square section is filled incompletly. In the eutectic alloys, the behaviour of the flow is similar to that of the alloys of wide solidification range, but the freezing of it begins at the flowing front.

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