Contact displacement

Stress relaxation, while aUied to creep, is different (20—23). Stress relaxation is the time-dependent decrease in load (stress) at the contact displacement resulting from connector mating. Here, the initial elastic strain in the spring contact is replaced by time-dependent microplastic flow. Creep, on the other hand, relates to time-dependent geometry change (strain or displacement) under fixed load, which is a condition that does not apply to coimectors. 

Decrease contact displacement to reduce wear Decrease contacting hy lowering mixing and collision frequency (e.g., mixer impeller speed, fluid-hed excess gas velocity, drum rotation speed). 

Decrease load and contact displacement for wear Decrease bed height to effect load and decrease excess gas velocity to lower collision frequency and mixing and therefore contacting. 

There are two product categories of displacement sensing technology. Whenever the moving target is mechanically connected to a sensor, it is referred to as a contact displacement sensor. The physical principles adapted for contact displacement sensors are primarily ... 

If the object to be measured cannot be mechanically attached to the moving target, does not permit contact or any external force, a non-contact displacement sensor has to be used. The physical principles for non-contact displacement sensors are primarily ... 

Decrease load to reduce wear. Decrease contact displacement to reduce wear. Lower formulation density. Decrease bed agitation and compaction forces (e.g., mixer impeller speed, fluid-bed height, bed weight, fluid-bed excess gas velocity). Decrease contacting by lowering mixing and collision frequency (e.g., mixer impeller speed, excess fluid-bed gas velocity, drum rotation speed). 

The possibility of applying copper deposition directly on top of TiN barrier via electrochemical method was studied. Previous report of using contact displacement to deposit copper was found chemically questionable. The copper deposition observed could be due to reaction between cupric ion and silicon underneath through cracks in the intermediate TiN layer. 

Since we are interested in the mechanism of copper deposition by contact displacement, we prepared three kinds of solution to ascertain the controlling factor. 

Obviously copper can be deposited by contact displacement on Si surface directly, but the reaction needs the assistance of fluoride ion. In fact M.K.Lee (5lalready observed this and proposed the following reaction,... 

A direct chemical analysis of the product after we dipped TiN powder in the solution for copper contact displacement indicates TiN can react with CuS04 solution but very slowly. Apparently Cu2 ions can readily be displaced by Si and Ti instead of TiN. 

Valery M.Dubin, Yosi Shacham-Diamand, Selective and blanket electroless Cu plating initiated by contact displacement for deep submicron via contact filling ,... 

Fig 6 TiN surface dipped in palladium contact displacement solution by X-ray mapping... 

FIGURE 17.9. Three types of wetting phenomena may occur, each with its own thermodynamic relationship. They are (a) adhesional wetting in which two surfaces make contact displacing a third phase, but without flow (Z>) spreading wetting, similar... 

Hamstad MA (1997) Improved signal-to-noise wideband acoustic/ultrasonic contact displacement sensors for wood and polymers. Wood and fibre science 29 (3) 239-248... 

Figure 5. Wear processes. Wear processes are divided into those which result from loss of form but not mass and those which result from loss of mass. The overall wear process for the latter involves debris detachment and out-of-contact displacement before the final mass wear occurs.

It is well known that dislocation etch pits on the surfaces of metals are produced in solutions of salts of other metals as a result of contact displacement reactions (53)(54). The size of pits formed by these solutions depends on the concentration of a salt and the time of etching. However, prolonged etching often leads to the precipitation of mono- or polycrystalline displaced metal at relatively more active sites where dissolution is faster than that at the rest of the surface. Subsequent etching can yield etch hillocks, as observed In the case of etching white tin in acidic solutions of CuSO. Whether etch hillocks or etch pits will be formed at dislocation sites Is determined by the exchange kinetics at the electric double layer and by the diffusion kinetics. 

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