Materials possible expansion mechanisms

These reamers have also more than one flute and have an incorporated expansion mechanism. This mechanism was developed to compensate the tool wear during the cutting process. The diameter of the tool can be expanded by an internal cone to readjust the requested tool diameter. The expansion mechanism works in the area of elastic deformation of the tool body material. The expanding mechanism is always of high precision. An adjustment of the tool diameter within 2 pm is possible. The targeted hole tolerance is IT6 and better. 

Piping joints shall be selected to suit the piping material, with consideration of joint tightness and mechanical strength under expected service and test conditions of pressure, temperature, and external loading. Layout of piping should, insofar as possible, minimize stress on joints, giving special consideration to stresses due to thermal expansion and operation of valves (particularly a valve at a free end). 

The mechanical and physical properties of the inhibiting material must be fairly similar to those of the propellant in order to minimize the differential expansion. In this respect the use of several layers with possibly different compositions is favorable. With long burning timers (more than 20 sec) the development of a reliable inhibitor poses a fairly difficult problem, especially with end-burning grains. 

BN fibers are used for reinforcing ceramic materials (e.g., Al203, Si3N4, SiC) to enhance mechanical properties as well as to extend the range of possible applications. They serve as reinforcement of organic polymers (e.g., epoxides, polyether-polyketones, polyphenylensulfides) which exhibit good thermal conductivity and low thermal expansion. 

Sometimes conventional welding or a mechanical joining process is just not possible. Substrate materials may be incompatible for metallurgical welding due to their thermal expansion coefficients, chemistry, or heat resistance. The end product may not be able to accept the bulk or shape required by mechanical fasteners. 

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