Catalytic Converter
The Catalytic Converter is one of the most effective emission control devices available. The Catalytic Converter processes exhaust to remove pollutants, achieving considerably lower emissions than is possible with in-cylinder techniques. Vehicles with catalytic converters require unleaded fuel, since lead forms deposits that poison the catalytic converter by blocking the access of exhaust gases to the catalyst. The catalytic converter comprises a ceramic support, a washcoat (usually aluminum oxide) to provide a very large surface area and a surface layer of precious metals (platinum, rhodium and palladium are most commonly used) to perform catalyst function.
(A.Faiz, C.Weaver, M. Walsh, Air pollution from motor vehicles: standards and Technologies for Controlling Emissions, p.67)
Workability
Workability is a vital aspect of the processing of materials, having posts in both material behaviour and process design. Whether a part can be produced by plastic deformation without cracking or the generation of other defects is of important economic consequence. Because of the complex natüre of the workability of metals, there is no single test can be used to evaluate it. Several laboratory tests have been developed that are useful in screening materials for workability, but in other instances, very specialized tests that are specific to the process are commonly used.
(G.E.Dieter, H.A.Kuhn, S. L. Semiatin, Handbook of workability and process design, p.1)
No comments:
Post a Comment