Mechanical stability grease

Calcium complex soap greases, obtained by the reaction of lime and a mixture of fatty acids and acetic acid. These greases offer good high temperature and anti-wear/extreme pressure properties related to the presence, in the soap, of calcium acetate that acts as solid lubricant they have good mechanical stability. 

Aluminum complex greases, obtained by the reaction of aluminum isopropylate with a mixture of benzoic acid and fatty acids. These greases have a remarkable resistance to water, very good adhesion to metallic surfaces, good mechanical stability properties and resistance to temperature. They are less common than the first two types. 

Greases Mechanical and rheological behavior and its persistence Consistency and viscosity Mechanical stability Oxidation resistance... 

Grease type of soap) Recommended maximum operating temperature (°C) Water resistance Mechanical stability... 

Power modules are integrated in electric and hybrid vehicles, for example, in order to connect the transistors of the power electronics to the heat sinks. The use of power modules is typical for power levels above one kilowatt (Hensler 2012). Power modules have electrical, mechanical, and thermal functions. The silicon chip, the bonds, and the copper layer form the electrical circuit. This electrical circuit is insulated from the rest of the module by means of an electrical insulator (typically ceramic). The insulation is applied to a heat spreader that ensures that heat is distributed uniformly within the module and that the heat is thus dissipated away from the chip. The heat spreader is typically made of copper and also provides mechanical stabilization. It is connected to the heat sink by a so-called thermal grease, and the heat sink in turn is cooled by means of a cooling medium (air or liquid). 

Within this category, the greases are divided into those based on simple soaps and those based on complex soaps. The latter generally have better high temperature and structural stability properties under high mechanical shear they also have higher resistance to water than their simple soap-based counterparts. 

CPA. Copolymer alloy membranes (CPAs) are made by alloying high molecular weight polymeries, plasticizers, special stabilizers, biocides, and antioxidants with poly(vinyl chloride) (PVC). The membrane is typically reinforced with polyester and comes in finished thicknesses of 0.75—1.5 mm and widths of 1.5—1.8 m. The primary installation method is mechanically fastened, but some fully adhered systems are also possible. The CPA membranes can exhibit long-term flexibiHty by alleviating migration of the polymeric plasticizers, and are chemically resistant and compatible with many oils and greases, animal fats, asphalt, and coal-tar pitch. The physical characteristics of a CPA membrane have been described (15). 

Mechanical properties (stiffness, impact, and shock resistance), electrical properties, clarity, ease of processing, sealing properties, dimensional stability, resistance to hydrocarbons and other organic liquids, resistance to plasticizers, greases, and oils are the characteristic properties desired. In its mechanical properties it approaches polycarbonate most closely. However, since polycarbonate is cheaper than Trogamid T, Trogamid T will be preferred only where polycarbonate cannot be used. 

Figure 13.18 The mechanism by which soap removes grease, (a) Grease (oily substance) is not soluble in water, (b) When soap is added to water, the nonpolar tails of soap molecules dissolve in grease, (c) The grease can be washed away when the polar heads of the soap molecules stabilize it in water.

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