Summary
    One of the initial stages in the Product-Process Development Cycle is the Conceptual Design stage. The Conceptual Design defines the physical concept of the product, including the product function basic principles as well as the identification of its geometric characteristics. A part design can be difficult to manufacture, causing defects or high and inadequate process parameters during the production process chosen for its forming. These defects imply changes in Process Planning which can increase significantly product’s time-to-market. Hence, it is essential to dispose of a possibility to estimate the product manufacturability and its final quality before it is produced, moreover, even before the Process Planning is done. An automatic assessment tool capable of offering a manufacturability report in a short time would represent an ideal assistant for that purpose.
    Such an assessment tool that relates the product design with its manufacturability should be knowledge-based. The incorporated knowledge is related to the physical processes that govern different production process stages. This knowledge allows the establishment of a strong product design-to-manufacturability relation and permits the estimation of the product viability even before it is produced. The assessment tool provides feedback information on design changes’ influence in the product manufacturability. The feedback information obtained during the very initial stage of Product-Process Development Cycle avoids additional costs necessary when the design changes necessity is discovered in the production stage. In injection forming processes, the most important manufacturability aspects are safe demoulding, a complete and uniform filling and a uniform part thickness distribution. In order to perform the manufacturability analysis, these aspects should be related to the part geometry.
    In this Ph.D. Thesis the bases of an automatic and integrated tool capable of manufacturability estimation of a part formed by Powder Injection Moulding process (PIM) is presented. PIM is a forming process that includes an injection stage which is why it shares the above mentioned manufacturability aspects of injection forming processes. The manufacturability estimation is done automatically, using a methodology developed on the synthesis of the product geometry influence on manufacturability through the manufacturability aspects. The methodology is based on use of the mid-plane part geometry representation which is found to be very suitable for the automatic assessment. As a result of this methodology application in form of different algorithms, certain process parameters related to the manufacturability aspects are estimated. Those parameters are used to calculate a number of manufacturability indices such as demoulding index, injection pressure index, partial cycle time index, welding line indicator and crack indicator. A higher value of these indices indicates higher part manufacturability. Additionally, feedback information about the part conflictive zones is accomplished and it serves as a design changes guide.