Roller Clutches are less noisy than toothed clutches. There is lesser engaging shock during engagement. Roller clutches can be operated at much higher speeds (up to 4 m/sec) than toothed cluthes (0.7 m/s). Their simple design and ease in manufacture make them convenient for use in uni-directional operation, despite a bigger size and rapid wear. The wear is minimized by using hardened inserts at the contact faces.
(Joshi P.H., Machine Tools Handbook: Design and Operation, pg.332, Kayra Ermutlu)
Mechanical Alloying
Mechanical alloying is a high energy dry ball milling process used to make composite metallic powders with a controlled fine microstructure. Powders of the desired composition are blended and then placed in a high energy ball mill. The intensive milling process repeatedly fractures and then rewelds the powder particles. During each collision with the grinding balls, the particles are plastically deformed to the extent that the surface oxides are broken, exposing clean metal surfaces.
On subsequent impacts, the clean surfaces are welded together. This cold welding process increases the size of the particles, while at the same time additional impacts are fracturing particles and reducing their size. As the process continues, the microstructure of the particles is continually being refined. Milling is continued until every powder particle contains the same composition as the starting mix.
(Campbell F.C., Manufacturing Technology for Aerospace Structural Materials, pg.232, Kayra Ermutlu)
Tape Forming
Tape formingis used to make thin ceramic parts like alumina substrates for integrated circuit chips and special capacitor. A thin layer of slip is laid on a flat carrier which can be a paper sheet or polymer film. A doctor blade controls the slip thickness, resulting in a tape that can be stamped into small shapes. These can be stacked or coiled for subsequent sintering.
(Ohring M., Engineering Materials Science, Part I, pg.420, Kayra Ermutlu)
Mechanical Overload
As the name implies, This type of fracture results when load applied exceeds the available strength of a component. This seems straight forward enough, but there are some subtleties. For example, "What is the available strength of a component?". Actually, it is a function of two things. It is derived from both the inherent strength of the material and how much of that material is available to carry the load. If the material strength is compromised (through alteration of its heat treatment, for example) then the strength of that component is not as intended. Similarly, if the amount of load bearing material is deminished (through corrosion or cracking) then the component is similarly weakened.
(Broker J.P., Hill P.F., Bicycle Accidents: Biomechanical, Engineering, and Legal Aspects, pg.242, Kayra Ermutlu)
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