| Autor: |
Kir'yanov, Yu. G., Zavina, T. A., Syrkin, V. G. |
| Zdroj: |
Powder Metallurgy and Metal Ceramics; February 1978, Vol. 17 Issue: 2 p110-112, 3p |
| Abstrakt: |
1.Phosphate film formation on the surfaces of carbonyl iron powder particles occurs through a heterogeneous first-order reaction which slows down with time as the film thickness grows.2.The mean rate of the phosphate film formation reaction depends on the concentration of orthophosphoric acid in acetone, the concentration of carbonyl iron powder in the liquid phase, and the temperature.3.The mean rate of the reaction attains its maximum value at an acid concentration in acetone of 0.01 g/ml (1.28 wt.%) and a CI powder concentration in the liquid phase of 2.5 g/ml.4.The degree of reactive transformation ranges from 24.8 to 32.1%, the reaction coming to an end after 9.2-9.6 sec.5.The kinetics of the CI powder phosphatizing reaction is not the limiting stage of the process, which can therefore be optimized by introducing improvements in the other stages.6.One of the principal processing parameters in the phosphatizing of CI powders is the concentration of orthophosphoric acid in acetone. Control over this parameter can be conveniently exercised by measuring the solution pH. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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