Why study the reaction of titanium plates with steam
Tests carried out in a vacuum apparatus with a quartz microbalance in the spring . Reading accuracy is 4 × 10 - sample surface g / cm . Mercury manometer measuring system connected to the reaction chamber using the pressure .
Titanium iodide as a sample . Breaking titanium strip cold rolled to a rod 0.7 mm thick . Then cut the strip size is 9 × 25 mm sample . In order to eventually remove surface dirt , before the test sample with a finely sandpaper and etched in 7% HNO3 solution in HF .
The tube is filled with distilled water and vacuum means connected to the plug and the device as a source of water vapor . In order to remove the dissolved grade 1 titanium sheet water gasification will remain for some time in the water under the stars . Samples were heated to a predetermined temperature in a vacuum after the tube with water and the system is turned on, and set up the equilibrium vapor pressure corresponds to the temperature in the system . When the system is full , the system is filled with water and cut off the tube , and then tested in a closed volume .
Under 800,850,900 and 950 ℃ and 14 mm Hg vapor pressure tested titanium plate and steam reaction .
Kinetics of these tests indicate that , in the beginning stage of the reaction , the reaction with water vapor titanium plates subject to the parabolic law . After the reaction started after a certain period of time becomes linear parabolic law rule.
In order to identify the effect of pressure on the reaction rate , once at 4 mm Hg pressure two experiments .
Titanium plate during the reaction and steam , and any of metals, and also the reaction gas , is composed by a number of successive stages , in which the main are: 1 ) titanium spring wire the gas molecules collide with the metal , 2 ) gas molecules adsorbed on the metal surface 3 ) the dissociation of the gas molecules , 4 ) through the surface of the film agent diffusion reaction product , 5 ) chemical reaction.
The reaction rate depends on the speed of the pro stage . It was found that the reaction pressure is reduced because the rate of 5 /6 and steam manganese remains unchanged , so it should be acknowledged that the reaction speed depends on the diffusion of the reagents through the surface of the membrane , grade 1 titanium wire since it is the only one speed stage and the gas pressure independent .
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