Abstract: This invention relates to a method of preparing anti-corrosive hybrid sol-gel film coating on zinc or zinc alloy coated metallic substrates comprising the steps of preparing a mixture of sol-gel from hydrolisable silicon alkoxides, sodium venadate solution combined with colloidal silica in a beaker and vigorously stirred; adding within 20 seconds of two separated phase formation between silica precursors and colloidal silica acetic acid or dilute nitric acid as a catalizer to initiate hydrolysis reaction of silicon alkoxides and condensation reaction in the sol gel composition, continuously stirring the mixture for about 24 hours to form a single phase solution, applying the solution on cleaned zinc or zinc alloy coated metal substrates to form a transparent sol-gel coating film and drying the coated substrates at 50° to 200° C. for 10 to 60 minutes.

Abstract: A method of joining components to a substrate by reflow soldering with non-rosin-based flux containing solder is disclosed comprising heating the solder in the presence of the components in a low oxidizing atmosphere.

Abstract: A single-step process is disclosed for hermetically sealing a glass to a metal having similar coefficients of thermal expansion without carrying out the conventional pretreatment steps of decarburization and oxidization by heating to at least the melting point of the glass in an atmosphere containing from about 0.5 to 2.5 volume percent of water vapor, 0 to about 5 volume percent of hydrogen gas and the balance an inert gas, such as nitrogen.

Abstract: Aluminum alloys suitable for fabrication into plate and fin type heat exchangers are subjected to a chemical etching procedure in order to improve the heat transfer efficiency thereof. Applicants have found that a high temperature heat treatment of an aluminum alloy plate material to produce a precipitate, followed by exposure to an etching composition, results in a heat exchanger surface modified by the formation of pits. The heat exchangers so modified may be advantageously used in the reboiler/condensor section of air separation units.

Abstract: Aluminum alloys suitable for fabrication into plate and fin type heat exchangers are subjected to a chemical etching procedure in order to improve the heat transfer efficiency thereof. Applicants have found that a high temperature heat treatment of an aluminum alloy plate material to produce a precipitate, followed by exposure to an etching composition, results in a heat exchanger surface modified by the formation of pits. The heat exchangers so modified may be advantageously used in the reboiler/condensor section of air separation units.