Introduction to composites and manufacturing processes

Non-cocoa fats are added to certain chocolates for a number of reasons. Their introduction was prompted by a sharp rise in the cost of cocoa butter in the 1960s which coincided with the emergence of technologies suitable to analyse butter composition and produce substitute fats. Principally, chocolate manufacture can be made more economical by using more stable processing conditions when other fats are added. The variations in processing required by changes in the chemical composition and physical properties of different batches of cocoa butters, and the effects of erratic harvests, can be ameliorated by the incorporation of the tailored non-cocoa fats. 

Obviously, to increase the load-carrying capacity of a material, it is necessary to increase the constants Tm, xm, and U0 and to reduce y. It is known [8], that the increase in U0 is promoted by an increased filling and its uniformity. Introduction of special additives (plasticizers, antioxidants, and others) to a composition, along with the manufacturing process and material structure, will have an essential influence on constants Tm, xm, and U0. 

Industrial concern for quality and process control, as well as in-service examination, has led to an increased demand for composite reliability inspection techniques. New and more sophisticated NDT techniques have been developed to meet this demand. However, there is still the view that the tried and tested conventional methods are generally more acceptable, their limitations understood and appreciated. Despite the development of new NDT techniques for composite examination, conventional NDT techniques will remain favoured to NDT engineers as they are expected to be accepted more readily [1]. The introduction of innovations, in addition to highly proven and accepted reliabilities in flaw detection, is significantly desirable to composite manufacturers and users. 

Today, FRCs are in use in a variety of structures, ranging from spacecraft and aircraft to buildings and bridges. FRCs find applications in construction industries, decking, window and door frames, sports equipment such as bicycle frames, baseball bats, exercise equipment, etc. They are also suited for many automotive applications. This wide use of composites has been facilitated by the introduction of new materials, improvements in manufacturing processes and developments of new analytical and testing methods. 

The introduction of LA into commercial detonators resulted in an unacceptably high level of explosions during manufacture and use and hence its use was discontinued until it could be prepared in less sensitive form. A number of methods have been used to prepare LA in a less sensitive form. The main control of properties is by synthesis rather than by any other approach. Lead azide compositions RD 1343 (improved CMC co-precipitated LA), RD 1352 (improved dextrinated LA) and Service lead azide (SLA) illustrate some modified LAs which are used depending on the requirements. Different processes developed for the modification of LA may be summarized as follows ... 

These innovations require an increase in the number of formulations to improve product quality (compounds), new shapes, and an increasing use of composite materials, nanomaterials and bioplastics. It is also necessary to rely on process innovations. The extruder is now considered not only as a tool for the manufacture of the polymer allowing, for example, the introduction of various loads, but as a... 

The technology of polyblends manufacturing forges ahead its development is directed to the simplification and cheapening of the production processes of composite materials with nanoparticles in their structure. However, new nanotechnologies develop very quickly what seemed impossible yesterday will be accessible to the introduction on a commercial scale tomorrow. The desired event of fast implementation of polyblends in mass production depends on the efficiency of cooperation between the scientists and the manufacturers in many respects. Today s high technology problems of applied character are successfully solved with the coordinated efforts of both the scientific and business worlds. 

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