EXPERIMENTAL DETERMINATION AND FORMULATION OF MATHEMATICAL MODEL FOR CONTACT DEFORMATION OF NYLON AND PVC
Keywords:
Contact Deformation, Nylon, PVCAbstract
The surfaces of the most engineering materials are unavoidably rough and contain geometric irregularities with feature sizes ranging over many length scales. The contact between rough surfaces is generally restricted to the tips of asperities. Consequently even a light mechanical load can cause localized surface plastic deformation and residual stress will be developed after unloading. The point contact between asperities renders the contact area negligibly small and can be considered tending to
zero. This implies stress at point of contact is infinite even under influence of light mechanical load. This infinite stress is responsible for material flow and consequently results in micro displacement. This phenomenon is called contact deformation. Micro displacement errors due to contact deformation and dimensional instability in members of precision machine tools like CNC’s are highly intolerable. The scope of present work is an experimental study in effect of load and surface roughness on nylon and polyvinyl chloride and the results analyzed to obtain a general equation. The mathematical model so developed is based on statically designed experiment.
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