Stainless steel, oxidation

Now we consider the isomer shift, which was first identified correctly by Kistner and Sunyar in 1960 in studying (15) the ferric oxide-stainless steel spectrum. A graphical summary of the origin of the isomer shift is given in Figure 7. The isomer shift arises from the fact that the nucleus is not a point source but interacts as a region of charge space... 

Corrosion of a surface may alter nucleate-boiling heat transfer in either direction. If the corroded surface is a good catalyst, the heat transfer rates can increase. Copper oxide is a better boiling surface for water than is copper (S2). On the other hand, oxidized stainless steel is sometimes better, but often poorer than unattacked stainless steel with water (B16). Oxidized chromium is a poor boiling surface for water compared with fresh chromium (J3). 

In Fig. 15 hydrogen desorption data from linear ramp thermal anneals of oxidized stainless steel are presented. 

Fig. 15. Linear ramp thermal desorption of oxidized stainless steel samples implanted with 300 eV hydrogen at room temperature (Clausing, R. E., et. al. in Ref.39), p. 573). The thermal desorption technique shows that (1) a large amount of hydrogen is adsorbed in or near the sample surface, (2) the hydrogen is easily desorbed...

On-board type oil deterioration pH sensor. Considering practical use as an on-board type pH sensor, it is desirable to use rigid materials for the electrodes which are thought not to be damaged due to mechanical vibrations of the engine. Therefore, oxidized stainless steel and lead electrode were selected as the pH-response electrode and the reference electrode, respectively. The signal of the newly developed sensor gradually increases as the deterioration of the oil... 

Polyoxyl 10 Oleyl Ether Free Ethylene Oxide Stainless Steel, 1.8 M x 3 mm I.D. (OD) S3 Helium 160 FID n-Butyl Chloride NF (19, p. 2498)... 

For some applications non-oxide, stainless steel supports appear interesting. This support does not suffer from the brittleness of ceramic supports and can be quite easily connected to other module components, but does not allow strongly oxidising conditions or high temperatures. 

Figure 10.2 shows clearly that at about 1000°C sodium oxide can oxidize stainless steel (the dashed line represents liquid sodium above its normal boiling point). A diagram of this kind shows not only that sodium can cause material transport of oxygen from a point of external contamination, but also that metallic zirconium is able to hot-trap the oxygen from the sodium stream. 

In dilute solution, perbromate is a sluggish oxidant at 25° and is slowly reduced by I- or Br- but not by Cl-. However, the 3M acid readily oxidizes stainless steel, and the 12M acid rapidly oxidizes Cl- and will explode in contact with tissue paper. Above 6M the solutions are erratically, but not explosively, unstable. 

Ast] Auger electron spectroscopy Analysis of a (Fe,Cr)203 oxide scale on an oxidized stainless steel... 

A special case of SAM formation on oxidized stainless steel was reported by Sukenik and coworkers [167]. The stainless steel surface was polished, washed, and sonicated, followed by exposure to air plasma for 1 h. A thin layer (ca. 3 nm) of Si02 was formed on the oxidized stainless steel by treatment with tetraalkylorthosil-icate. This layer served as an anchor for subsequent attachment of alkyltrialkoxysi-lane films. 

The reactants and products were analyzed by standard gas chromatographic techniques. In all cases the added surface is 1/16" oxidized stainless steel rods set parallel to the direction of gas flow. 

Upon placing an oxidized stainless steel surface in the reactor, oxygen absent, the rate decreases and the activation energy is increased which makes ethylene unique with respect to the other hydrocarbons of this paper. Due to the lability of the triple bond to surface effects (see section on propylene), there is a large uncertainty in the surface data for ethylene since carbon deposition could markedly alter the calculated rate constants. 

Figure 3. Percent propane converted to products. Conversions varied with temperature in °C oxidized stainless steel surface surface-to-volume ratio, 0.7 Cm reaction time 0.22 sec.

Effect of an Oxidized Stainless Steel Surface on the Propane-Oxygen Reaction... 

To avoid classical corrosion mechanisms, ceramics and composite materials have also been tested (some of these materials are also common components in heterogeneous catalysts). An alumina reactor for SCWO was proposed among ceramic materials only a few aluminas and zirconias did not corrode severely, whereas SiC or BN lost up to 90% by weight under SCWO conditions in the presence of HCl. The combination of steel and ceramic coatings should theoretically provide high-pressure stability and improved corrosion resistance, but only slight improvements were reported for stainless steel SS316 coated with sol-gel-prepared Ti, Zr or Hf oxides, stainless steel SUS-304 with TiN or Ni alloys and ceramics. Often the adhesion of the ceramic layer on the steel surface is not sufficient. 

Apart from the corrosion caused by oxidants, stainless steels in chloride melts can be affected by IGC. Austenite steels can develop IGC after prolonged heating at 450-850 °C [22, 23]. The most valid reason for the appearance of IGC in austenite steels is a depletion of grain boundaries in chromium due to formation of chromium carbides [22-25]. 

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