Saturday, March 26, 2011

Ali Utku Gökçe-030060060-7th week

Abrasive Saw:
Saw machines are also made with circular abresive or metal-cutting wheels. The abrasive saw may be used for high-speed cutting where a narrow saw kerf is desirable or when very hard materials must be cut. One advantage of the abrasive saw is its ability to cut a variety of materials-from soft aluminum to case-hardened steels. (cutting a variety of metals on the bando r the power hacksaw requires blade and speed changes.) A disadvantage of the abrasive saw is the expense of abrasive discs. Many companies use this saw only when versatility is needed. The abrasive saw is usually found in the grinding room where abrasive particles can be contained, but may also be used in the shop for general-purpose cutting. Metal cutting saws with teeth, also known as cold saws, are used for precision cutoff operations, cutting saw kerfs, slitting metal, and other manufacturing uses.
(David A. Madsen, Print Reading For Engineering And Manufacturing Technology, P.120)

Band Saw:
The modern woodworker need tools that are simple yet versatile. These tools should do a large variety of jobs without expensive or complex jigs. There is no operation more basic to woodworking than sawing, and the versatile band saw can do all types of sawing. It will cut wood thick or thin and square or round. It will cuth both curves and straight lines. It will resaw thin veneer and make tight scroll-saw-type cuts. A skilled user can quickly turn a humble log into four perfectly matched Quenn Anne chair legs,. And with a simple band saw jig, he can cut through dove tails for a box or a drawer presicely and efficiently with aminimum of setup. In fact, a band sawn dovetail box can  be finished before a router jig can be properly adjusted fort he same operation. The band saw dovetail jig doesn’t cost any thing either, just a little time and some scrap wood.
There are many reasons why a band saw should be the first power tool a person should learn to operate. To use a term coined in computer jargon, the band saw is user friendly. It is quiet and easy to use. Women often comment that it reminds them of a sewing machine. It can ben also be used for a wide range of functions.
(Mark Duginske, Band Saw Handbook, page 5)


Lemo Connectors:
The lemo connector plug locks down when pushed into a receptable. An upward force is required on an outer knurled collet out the plug to disengage it. Both the laser fiber and the collection fiber bundles are terminated in the CPT at the Raman probe with a Lemo connector. The lemo connectors are attached to the ARA electrical cables by means of a 26 gauge wire loop, which in turns is connected to the Lemo fiber optic release collet. The connectors are released when the wires, terminated in 30 wire Lemo friction fitted connector, are retrieved from the cone penetrometer pipe. Pull testing by ARA at a distance of 60ft. Demonstrated the ease of optical cable connector release, requiring no more than 2N of pull force. The fiber cables are jacketed in 3.8 mm O.D. Hytel composite material with Kevlar fiber reinforcement. This material is both durable and flexible, and can easily withstand the temparature requirements of the tank environment.
(Antonio Joseph Ricco, Chemical And Biological Sensors and Analytical Electrochemical Methods, Page 1071)

Martensitic tranformation:
A martensitic transformation is a structural phase transformation of the diffusionless and cooprative type, where the rearrangement of atoms occurs with relatively small displacements compared to inatomic distancesç There is a rigorous crystallographic connection between the lattices of the initial and final phases. The trasnsformation is of the first order. The martensitic transformation is called thermoelastic, when it is thermally reversible.

During martensitic transformation, the high-temperature phase,called austenit, transforms to the low- temperature phase, called martensite. As it is a firts-order structural phase transformation, the high-temperature asutenite and the low- temperature martensitic phases coexist in a specific temperature range. This is due to the elastic strains that accompany the nucleation and growth of the martensitic or austenitic phase. The austenite-martensite phase boundaries are fully or partially coherent. The elastic strains due to teh martensitic transformation increase with increasing martensite fraction. To compensate the transformation strains, different crystallographic domains are formed within the martensite. Macroscopically, they are often visible as paralel bands on the sample surface.

(J. Ping Liu, Nanoscale Magnetic Materials And Applications, p. 401)



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