Technology & Innovation Hydro-forming Hydro-forming uses fluid pressure in place of the punch in a conventional tool set to form the part into the desired shape of the die. The technique is very useful for producing whole components that would otherwise be made from multiple stampings joined together. For example, a typical chassis component that would normally be made by pressing up to six channel sections and joining by spot welding can be hydro-formed as a single part. Considerable mass savings are possible through eliminating the flanges required for welding and using thinner steel. Yet stiffness is maintained owing
Lightweight Connecting Rod Connecting rods are dynamic engine components under a great deal of stress and the way they are designed is determined to a great extent by their vibration resistance and operational strength. The component parts of crankshaft, connecting rod, piston and piston pin from the engines crank drive. When weight is reduced in oscillating masses, this spells out smellers mass forces, which has a positive impact on dynamic motor properties, fuel consumption and mechanical strain in the crank drive. This is the reason why lighter crankshafts offer new ways to design the entire subassembly of the crank drive. The changed strain placed on the connecting rods holds the promise of new opportunities for lightweight connecting rod design and the general connecting rod design may be analysis with a closed or open bridge between the small and large eye.
to the elimination of the discontinuous spot-welded joints. This new process, popularised by design studies which suggest that automobiles can be made much lighter by using hydro-formed components made of steel. Structural strength and stiffness can be improved and the tooling costs reduced because several components can be consolidated into one hydro-formed part. Components manufactured by forming can springback (the undergo elastic distortion on removing the component from the die). This effect is apparently smaller in hydro-formed components.
Super LSD
Another area of application for numerical simulations is assessing and evaluating mechanical and thermal stability of layer-substrate composites. Beyond this, simulations are also useful for achieving relevant material characteristic quantities in particular of failure parameters. This is the reason why several research projects at the Fraunhofer IWU are concentrating on simulating test processes for characterising material parameters and modeling damage properties of layers (layer delamination and crack formation) where simulation calculations are used in combination with special experiments for determining unknown failure parameters. One typical area of application is enhancing layer thicknesses to achieve the desired strength and avoid critical concentrations of stress in the layersubstrate interface.
Milling Thermally Sprayed Hard Metals
Process Automation Layer-Substrate Enhancement It is becoming increasingly desirable to use wearing protection coatings even with hydroforming tools. There are combined stresses due to the high level of contact pressure and friction shearing stress that makes it especially important to design it suitable to the type of loading and coating while applying the tool geometry and properties of the combination of layers and substrate.
Performance characteristics with nonlinear interrelationships Performance characteristics with non-linear interrelationships are estimated from test data and generate higher dimensional maps. This technique is also used in the “Virtual Reference Grinding” project, which was awarded the FraunhoferGesellschaft’s Joseph von Fraunhofer prize, to eliminate unevenness in large dry cylinders.
Innovative Super Limited Slip Differential (LSD) is the latest effective technology in front and rear axle/trans-axle applications, offering robust performance and versatility for front-wheel-drive, all-wheeldrive, and rear-wheel-drive drivelines. Super LSD is a cost effective compact torque-sensing limited slip differential design which improves vehicle traction and handling. It is lightweight and reliable and is easily packaged in place of an open differential and is compatible with AFT and gear oils.
Using hard metal in tool and mold making frequently appears to be uneconomical due to the high level of material and machining costs. Previous options have not offered any form of efficient or economic hard metal machining with complex-contour geometries. State-of-the-art production techniques such as high-velocity oxy fuel enable us to apply the hard metal material onto highly stressed tool zones which makes it possible to measurably improve protection against wear and tear. These layers have hardnesses in excess of 1,000 HV, giving them approximately the same properties as sintered hard metals, although they require a final finishing in spite of a high level of dimensional accuracy. A new and even highly economical machining option is milling thermally sprayed hard metals where setting up the process and selecting tools in alignment with the technique make it possible to measurably boost economy and flexibility. We were able to document a 60 per cent reduction in costs for hard metal machining with geometrically intricate contours in comparison to conventional techniques (such as contour grinding or electric discharge machining – EDM). Finally, milling of hard metal with super hard cutting materials not only generates a virtually damage-free edge zone, but also excellent surface qualities.
Courtesy: Fraunhofer Institute For achine Tool and Forming technology IWT
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MODERN MACHINE TOOLS - January 2012