Adding Flake Aluminum

At this point we can explain a trick used by glitter experts like Bill Withrow and Jerry Taylor. Charcoal is not the only material which can retard spritzel separation from the stars and create nucleation effects for larger spritzel formation. Small quantities of selected large flake aluminum do a betterjob when spritzels are desired to produce very long delays. Naturally, too much of these aluminums can cause the entire star to become one giant spritzel that never makes a spritz reaction. Best results are obtained in stars where these flakes, if rotated about their centers, would 

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Flake aluminum is made by milling other particle shapes. The impacts during milling will cause the flakes to stick together, unless a lubricant is added. 

A number of accessory materials and processing acids other than the foregoing have been mentioned in various places earlier some more must be added here to complete the picture. Manufactwing aids that remain with the finished materials are stearic or oleic acid in flaked aluminum or stainless steel flakes. Surface protection of metal powders has been cited in the preceding chapter. It may be performed by the manufacturer or by the user. 

The solid is in the form of flakes that have significant variability in particle size. The reaction is highly exothermic. It uses a catalyst of aluminum chloride and is conducted at about 383 K and 25.8 atm, but both temperature and pressure vary during the batch cycle. Since TML is an explosive, some toluene is added with the reactor charge to serve as a moderator. 

Six grams of 42% nickel, 58 % aluminum catalyst powder, all of which would pass a 150 mesh screen, was mechanically mixed in o porcelain mortar with ten grams of the elemental nickel powder for fifteen minutes. The calculated nickel content of the nickel aluminum powder was 2.52 grams, so that the added nickel was practically four times the nickel contained in the nickel aluminum alloy. The added nickel was not combined chemically with the aluminum, but was thoroughly mixed mechanically with the nickel aluminum powder. The six grams of 42% nickel, 58% aluminum powder had a calculated content of 3.48 grams of aluminum. Seven grams of 76% flake sodium hydroxide were used to make a 25% sodium hydroxide water solution. Potassium hydroxide or other caustic alkali solution may be used in place of sodium hydroxide and nickel carbonyl powder may be used in place of elemental nickel powder. Also, a nickel silicon alloy or an alloy of nickel with another alkali soluble metal may be used in place of the nickel aluminum alloy. 

The optimum pH for flocculation is about 6.5 to 7.5 for aluminum salts and about 8.5 for iron salts. If the natural alkali content of the untreated water is insufficient to neutralize the acid formed, alkali has to be added (e.g. calcium hydroxide or sodium hydroxide). In addition flocculation aids such as poly(acrylamide) or starch derivatives may be added (not in the case of potable water production). When aluminum sulfate Al2(S04)3 I8H2O is used 10 to 30 g/m- is added. The very fine hydroxide flakes which precipitate are positively charged and adsorb the negatively charged colloidal organic materials and clay particles. 

Metallic flakes are added to colorants to give them a metallic sheen. Aluminum flakes give a silvery sheen and also improve UV stability and impermeability. Bronze flakes can... 

Metallic pigments n. A class of pigments consisting of thin opaque aluminum flakes or copper alloy flakes. Added to plastics, they produce unusual silvery and other metal-hke attractive effects. 

Work by Motohashi and Shibata (1986) showed that similar 22% aluminum coatings from a bath to which was added approximately 0.1-0.3% Si showed good formability, coating adhesion, and flaking behavior, as well as corrosion resistance and damping capacity. The coating had a fine, equiaxial structure, a property that has a favorable effect on superplasticity and damping of vibration. 

Aluminum flakes are usually added to bituminous coatings, but these flakes have also been added to epoxy systems to act as active anticorrosive agents [9]. Normally, the buildup of a protective system is as follows ... 

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