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TIN Coating(First&Best) [Coating Type]

Due to their attractive properties, TIN coatings have been extensively used in various field of application. This nitride of transition metal has a high melting point, a high hardness value, advantageous optical properties and metallic conductivity. Coating of cutting tool for increasing wear resistance is probably the best known application. More specific examples of TIN utilization include diffusion barriers for semiconductors or filtering by ultra fine particles. TIN coating on glass is also popular for the production of decorative panels in architecture or solar glass in automotive industry.

(Hans K. Pulker,H. Schmidt, M. A. Aegerter, Coatings on Glass 1998,ICCG, pg. 307)

There is no previous definition.


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Burr (New&better) [Kind of undesired deformation]

Burr is formed as a result of plastic deformation in metal cutting and blanking operation, which is undesirable in manufacturing and has great influence on the accuracy of the parts. To remove or prevent these burrs effectively, burr must be measured with accuracy. For the burrs formed in machining are irregular and very sharp  in shape, it is usually very difficult to measure burr accurately, ıf the geometry of the burr is measured properly, the proper deburring method or processes can be recommended. Burrs are formed along the edge periphery, generally non-uniform and usually contain thin and sharp peaks. The height of the burr formed in precise and micro drill may vary from thousands to few microns while the hole size usually are of ten to one tenth millimeters in diameters. Specially in drilling at inclined exit surface, burr height distribution is different as in Fig 1 below.

( Jan C. Aurich, David Dornfeld, Burrs - Analysis, Control and Removal, Pg. 158)

Burr(previous)

At the top of the cut surface isa region called the rollover. This corresponds to the depression made by the punch in the work prior to cutting. It is where initial plastic deformation occured in the work. Just below the rollover is a relatively smooth region called the burnish. This results from penetration of the punch into the work before fracture began. Beneath the burnish is the fractured zone, a relatively rough surface of the cut edge where continued downward movement of the punch caused fracture of the metal. Finally, at the at the bottom of the edge is a burr, a sharp corner on the edge caused by elongation of the meatl during final seperation of the two pieces.

(Fundamentals of modern manufacturing: Materials,Processes, and Systems, Yazar: Mikell Groover, Page 445)



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Fluidized Bed(first&best) [Coating Method]

The fluid-bed method of wet granulation is well known in the pharmaceutical and other industries as a one-step, enclosed operation. Because several ingredients can be mixed,

granulated, and dried in the same vessel, the technique reduces material handling and shortens process times compared with other wet granulation processes. In addition to granulation for tableting, the fluid-bed top-spray method produces highly dispersible granules with a characteristic porous structure that enhances wettability. Such granules are

used in powdered food, nutritional, and chemical products.  The fluid-bed process often is used for coating and powdered layering (pelletizing) applications. Spray coating can be used for all fluid bed systems, be it in batch or continuous operation or if the film is applied from a

sprayed solution, suspension or hot melt. For this processing option the parameters have to be chosen to avoid agglomeration, i.e. liquid bridges between the air suspended particles . If spraying a solution or suspension the liquid only serves as a vehicle to deliver the coating material to the surface of the substrate. For hot melt coating the droplets must be small enough not to form solid bridges. The quality of the coating extensively depends on the statistical residence time of the particles in the coating zone. For a classic fluid bed unit only top-spray coating is possible. Bottom-spray or tangential-spray coating inserts can also be hosted by means of the relevant technical provisions.
 

  (Saurabh Srivastava, Garima Mishra, Fluid Bed Technology: Overview and Parameters for Process Selection Pg. 239)
There is no previous definition 

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Flocking Coating(new&better) [Coating Type]

Flock Coating is a widely used process to create a textile-like texture on substrates of various shapes and materials. In the processi flock fibers-short fibers typically 1-3mm long-are oriented and accelerated towards the substrate by means of an electric field. Impacting fibers are stuck to the substrate surface by an appropriate adhesive. The technique is applied to products as diverse as textiles, plastic car interior components, floor coverings or furniture with the objective to provide decorative, but also functional effects, e.g., to reduce friction. Substrate materials range from polymers to metals as well as ceramics.

(K. L. Mittal, Contact Angle, Wettability and Adhesion, pg. 326)

Flocking Coating(previous)

After , the profile is taken to an air-conditioned chamber where is passes through one or several electrostatic flock coating units. The viscosty and tempurature of the adhesive and the condition of flock cating determines the success of procedure and require constant monitoring. The flock must be air-conditioned before use . After flock coating , the profile passes through a drying line. Here any remaining solvent is evaporated and adhesive crosslinked.

(Continuous Vulcanisation of Elastomer Profiles ; A. Hill , pg ; 35 , 1997)
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Arrowhead Crack(firt&best) [Kind of Crack]

This defect is an internal crack that develops as a result of tensile stress along the centerline of the workpart during extrusion. Although tensile stresses may seem likely in a compression process such as extrusion, they tend to occur under conditions that cause large deformation in the regions of the work way from the central axis. The significant material movement in these outer regions stractches the material along the center of the work. If stresses are great enough, bursting occurs. Conditions that promote centerburst are high die angles, low extrusion ratios, and impurities in the work metal that serve as starting points for crack defects. The difficult aspect of centerburst is its detection. It is an internal defect that is usually not noticeable by visual observation. Other names sometimes used for this defect include arrowhead fracture, center cracking and chevron cracking.

(Mikell P. Groover, Fundamentals of Modern Manufacturing: Materials, Processes, and Systems, Pg. 430)

There is no previous definition.