Titanium solvent cleaning

Surface cleaning/etches. As with aluminum and titanium, the most critical test for bonded steel joints is durability in hostile (i.e., humid) environments. The fact that the problem is a serious one for steel was illustrated in a study [117] that compared solvent cleaned (smooth) 1010 cold-rolled steel surfaces with FPL aluminum (microrough) substrates. Although the dry lap-shear strengths were not markedly different, stressed lap-shear joints of steel adherends that were exposed to a humid environment failed in less than 30 days, whereas the aluminum joints lasted for more than 3000 days. 

For vapor degreasing, toluene rather than a chlorinated solvent should be used, because residues fium chlorinated solvents (and also from sflicated solvents) may contribute to cracking of titanium weldments. Solvent cleaning is fi equently used, especially for large components that cannot conveniently be placed in a vapor... 

Fluorotitanic acid is used as a metal surface cleaning agent, as a catalyst, and as an aluminum finishing solvent (see Metal surface treatments). Fluorotitanates are used in abrasive grinding wheels and for incorporating titanium into aluminum aHoys (see Abrasives Aluminumand aluminum alloys). 

Materials of Construction and Operational Stress. Before a centrifugal separation device is chosen, the corrosive characteristics of the Hquid and soHds as weU as the cleaning and saniti2ing solutions must be deterrnined. A wide variety of materials may be used. Most centrifuges are austenitic stainless steels however, many are made of ordinary steel, mbber or plastic coated steel. Monel, HasteUoy, titanium, duplex stainless steel, and others. The solvents present and of course the temperature environment must be considered in elastomers and plastics, including composites. 

These metal analyses indicate a marked reduction of both titanium and iron in the dialytic extract relative to both the coal and the soxhlet extract. The question remaining is, how much of this metal is background It should be noted here that attainment of good trace element analyses in the low ppm range requires very careful experimental precautions and replicate analyses. This particular experiment is, by its nature, difficult to conduct in a scrupulous "trace element clean" manner. However, if it is assumed that contamination from any source (solvents, glassware, utensils, etc.) will usually add to the concentration of metal, we can use the metal content determined in the dialyzate as an upper limit for soluble metals content. The higher iron and titanium concentrations in the soxhlet extract indicate that these metals may be associated with material which is not truly soluble, such as microparticulate mineral matter. 

Ordinary cleaners and solvents such as isopropyl alcohol and acetone are used on titanium. Halogen compoimds, such as trichlorethylene, should not be used, unless the titanium is pickled in acid after deaning. Titanium that has been straightened or formed with tools made of lead or low-melting alloy should be cleaned in nitric add. (These tool materials are not recommended for forming titanium). 

Removal of grease, oil, and other shop soils fi om titanium parts is normally accomplished with the same type of equipment and the same cleaning procedures used for stainless steel and high-temperature alloy components. Non-chlorinated solvents or alkaline deaners are recommended. 

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