Deformation of Copper Plates

A finite-element thermal-stress model of continuous casting mold is conducted to predict deformation of copper plates and its change with different cooling structure. The results show that deformation behavior of copper plates is mainly governed by cooling structure and thermal-mechanical conditions, deformation amount is related to structure geometry, and a small deformation mutation occurs in cooper-nickel boundary due to different properties. The maximum deformation of hot surface centricities of wide face locate at 100 mm below meniscus and that of narrow face locate at meniscus and terminal of water slots and sigiiiiicant curvature fluctuations on both sides of copper-nickel boundary. The maximum deformation of centricities is increased up to 0.05 mm with thickness increment 5 mm of copper plates, and maximum deformations are only depressed 0.01 mm and 0.02 mm with increments of 1 mm nickel layer thickness and 2 mm water slot depth respectively. 

The effect of thickness of mold copper plates on deformation of hot surface centricities is shown in Figure 3. The maximum occurs in position 100 mm below meniscus in wide face, while two peaks appear in narrow face including not only below meniscus, but also at copper-nickel boundary. The deformation is increased with thickness of copper plates and greater thickness leads to significant increment. The maximum deformations are promoted 0.03 mm and 0.06 mm in wide face and 0.03 mm and 0.05 mm in narrow face when thickness of copper plates is increased from 30 mm to 35 mm and from 45 mm to 50 mm, reqtectively. The high profile curvature in meniscus and near water slot terminals reveals that primary cooling and heat flux have greater impact on deformation of copper plates. However, property difference of copper and nickel has little effeet on deformation, and a small protrusion appears at copper-nickel boundary with thin eopper plates and oiily becomes apparent with thickness of 45 mm or more. 

The effect of thickness of nickel layers on deformation of hot surface centricities is shown in Figure 4. The nickel layer is too fliin to affect deformation of copper plates significantly, and almost no impact on wide face, while similar is that impact on narrow face is still relatively obvious. The deformation is reduced with thickness of nickel layers in region above copper-... 

The deformation of copper plates presented specific regularity subject to cooling structure, mold geometry and heat-transfer conditions and maximums are 0.34 mm and 0.4 mm on wide and narrow face reflectively and appeared m meniscus. 

DEFORMATION SIMULATION OF COPPER PLATES OF SLAB CONTINUOUS CASTING MOLD... 

The deformation is increased with thickness of copper plates. The pnmary cooling and heat flux have greater impact on deformation, while property difference of copper and nickel has little effect. 

Deformation Simulation of Copper Plates of Slab Continuous... 

Silver is often preferred as an undercoat for rhodium by reason of its high electrical conductivity. A further advantage of silver in the case of the thicker rhodium deposits (0-0025 mm) applied to electrical contacts for wear resistance is that the use of a relatively soft undercoat permits some stress relief of the rhodium deposit by plastic deformation of the under-layer, and hence reduces the tendency to cracking , with a corresponding improvement in protective value. Nickel, on the other hand, may be employed to provide a measure of mechanical support, and hence enhanced wear resistance, for a thin rhodium deposit. A nickel undercoating is so used on copper printed connectors, where the thickness of rhodium that may be applied from conventional electrolytes is limited by the tendency of the plating solution to attack the copper/laminate adhesive, and by the lifting effect of internal stress in the rhodium deposit. 

Figure 2. Deformation on hot surface of mold copper plates (a) wide face (b) narrow face Effect of Cooling Structure...

A popular connection system consists of square metal pins, usually 0.064 cm (0.025 in.) in size, that are pressed into holes drilled in a printed circuit board. The holes are copper (qv) plated on the insides and interconnect conductors on the top and bottom faces of the board. Multilayer boards have interior circuits that may also be interconnected in this way. The pias have either a soHd shank or a deformable (compHant) cross section where the pias joia the board (Fig. 2). Separable connectors or soldedess wraps (Fig. 3) engage the ends of the pias. One end of the pia can be the contact and spring of a separable connector. 

An EFP uses the action of the explosive s detonation wave (and to a lesser extent the propulsive effect of its detonation products) to project and deform a plate or dish of ductile metal (such as copper or tantalum) into a compact, high-velocity projectile, commonly called the slug (Fig. 7.7). This slug (one projectile with homogeneous velocity) is projected towards the target at about two kilometers per second. The main advantage of the EFP over a conventional shaped charge is... 

Comparison of ACAs with Hard and Soft Fitters. Kishimoto and coworkers reported (15) ACA pastes using two different fillers Au-coated rubber particles (soft) and nickel particles (hard). The ACAs were used to bond a flip chip with Au plated bumps to a board with copper metallization. With the application of pressure, the soft particles were brought into contact with surface pads and were deformed, which lowered this contact resistance. The hard particles, however, deformed the bumps and pads, and thus were also in intimate contact with the surfaces to help reduce this contact resistance. Their study showed that their choice of both hard and soft flllers in ACA materials had similar voltage-current behavior, and both exhibited stable contact resistance values after 1000 cycles of thermal cycling and 1200 h of 85°C/85% RH aging conditions (15). 

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