Joining techniques in engineering are of major importance. Innovations in the field of composites now allows design of nanomaterials with tailored properties. This book adresses techniques for similar and dissimilar joining, characterization of joint structures and damage prediction by simulation. A special focus is laid on welding of lightweight structures, which are of special economic interest for aeronautical and automotive applications.

Recycling of waste PE plastic converts them from one form to other which remains in environment and creates the environmental pollution . Major attention of this work is given for the conversion of waste PE plastic to other products, which will not create pollution in the environment. The conversion is done with eco-friendly method. Pyrolysis (thermal cracking) of plastic waste is possible to obtain a mixture of hydrocarbons, working at atmospheric pressure and moderate temperatures.Pyrolysis by Chemical Vapour Deposition (CVD) yields relatively narrow molecular weight distribution of hydrocarbons and can improve the selectivity in products obtained. Thus, the CVD pyrolysis is an environmentally friendly process, which is economically viable too.