Stainless steel surface preparation

Coupons of Type 304 stainless steel were prepared by mechanical abrasion and rinsed with methanol. Each sample was analyzed by XPS prior to treatment to ensure that no detectable casually-introduced chlorine was present. Two separate series of laboratory experiments were done one series (a) followed the effects of short-term contact between chlorocarbon and the alloy surface, a second series (b) investigated the effects of prolonged vapor and liquid contact with the alloy in a glass refluxer. In series (a) the clean alloy surface was swabbed using trichloroethane-soaked tissue and immediately inserted into the vacuum chamber of an XPS spectrometer for analysis. After analysis, the same coupon was exposed to the atmosphere for periods of 72 and 336 hours... 

Nitric acid is used by the steel industry to remove surface oxides (pickling) of stainless steels, to brighten and clean surfaces after salt-bath descaling and to prepare stainless steel surfaces for corrosion resistance (passivation). 

To examine the ability of membranes to prepare samples with known contaminants, we contaminated the above peptide and protein solution with 5% glycerol and 500 mM NaCl. In addition to preventing effective crystallization of analyte samples with matrix on conventional stainless steel surfaces, glycerol and sodium contaminants are frequently present in biological samples. Doped samples were prepared for MALDI-TOF analysis by saturating the membrane with MeOH, immediately followed by the addition of 1 ul of the sample. The membrane was washed 3 times with 3-6 ml 70% methanol in water and allowed to dry after each wash. Once dry, lul saturated matrix solution was added to the sample spot. 

The present results support the general conclusion by Baker and Chludzinski (10T that certain surfaces can minimize coke formation on the surface. In the present case/ aluminized stainless steels as prepared by Alon Processing/ Inc. retained their surface characteristics over at least two coking sequences. It is known in addition that a tube prepared by Alon Processing was used successfully in an ethylene coil for at least a year and that appreciable aluminum was still present on the surface at the... 

Smooth surfaces of each polymer were also prepared (without additives) by pressing samples of the powdered polymers against a highly polished stainless steel surface in a Carver press at 16,000 p.s.i. Circular disks 1 inch in diameter and weighing several grams were formed in this way. PS and the PVeC copolymer were compressed at room temperature, PAM at 120° C.,and PMMA at 150° C. The pressure was maintained until smooth polymer surfaces were obtained. The mold and stainless steel piston were cleaned prior to use, so that contact angles could be measured on the polymer surfaces without further surface treatment. 

Mechanical preparation techniques such as grinding can introduce significant cold work into the surface layers e.g. the pitting resistance of ground austenitic [3] and ferritic stainless steel surfaces [4] has been shown to be inferior to that of electropolished surfaces. This was attributed to the presence of cold worked surface layers from grinding, although chemical or electrochemical surface treatments can preferentially remove less resistant phases, e.g.inclusions, which would otherwise be responsible for an inferior corrosion performance. ... 

Additional precautions must be taken when laminating label materials to metal or other surfaces that can be contaminated by heavy debris or hydrocarbon residues. If grease, oils, or wax-based substances are present at the surface, solvents such as denatured alcohol, heptanes, xylene, or ethyl acetate can be effective as a first phase for preparing surfaces resistant to solvents. The final phase is recommended to be a final wipe with isopropyl alcohol until the surface is dry. Temperature is also an adhesion determinant. Stainless steel surfaces, for example, will maintain low surface temperatures for a longer period of time compared to other substrates. Preheating the surface of these metals with flame burner treatment prior to film label lamination will improve adhesive wet-out to metal surfaces. It is advisable that hydrocarbon oils be removed from these surfaces prior to initiating label contact. 

Synthetic Marble. Synthetic marble-like resin products are prepared by casting or molding a highly filled monomer mixture or monomer—polymer symp. When only one smooth surface is required, a continuous casting process using only one endless stainless steel belt can be used (52,53). Typically on the order of 60 wt % inorganic filler is used. The inorganic fillers, such as aluminum hydroxide, calcium carbonate, etc, are selected on the basis of cost, and such properties as the translucence, chemical and water resistance, and ease of subsequent fabrication (54,55). 

Deposition by metal spraying can also be used for the reclamation of worn parts in this case, surface preparation is often accomplished by machining, i.e. by cutting a rough thread on the surface or by increasing the surface area of the part by grooving. Such methods. are not, however, normally used in corrosion prevention, except in the case of pump rods, which can be built up with nickel or stainless steel. 

The metal plates to be coated with Raney nickel were type 304 stainless steel. Plate surfaces were prepared by sand blasting with an iron-free... 

Specimens were prepared by depositing aliquots (ca. 1-5 pL) of toluene solutions containing the samples onto the surface of a stainless steel target. After the solvent was... 

The preparations were carried out as usual in a three necked flask fitted with a stainless steel stirrer, condenser, and nitrogen inlet (10,11). The solvents and dichlorldes were added by syringe. The sodium was added as a freshly cut block and, prior to the reaction, melted in the refluxing solvent and stirred to form sand. The overall surface area of the sodium could be controlled by the stirrer speed. When necessary the stirrer speed was measured by a tachometer. 

Table IV shows X-ray data (55) on the homogeneity of Pd-Ag films prepared by simultaneous evaporation from separate sources, either in conventional vacuum or in UHV, with the substrate maintained at 0°C. The second group of films was prepared using a stainless steel system incorporating a large (100 1/sec) getter-ion pump, sorption trap, etc., but deposited inside a glass vessel. By the tests of homogeneity adopted, alloy films evaporated in conventional vacuum were not satisfactory, i.e., the lattice constants were generally outside the limits of the experimental error, 0.004 A, and the X-ray line profiles were not always symmetrical. In contrast, alloy films evaporated in UHV were satisfactorily homogeneous. Further, electron micrographs showed that these latter films were reasonably unsintered and thus, this method provides clean Pd-Ag alloy films with the required characteristics for surface studies.

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