Methodology to implement CAE validation in repair & redesign parts process of plastic injection molds

Repairs and redesigns for plastic injection molding parts generally is a short and straightforward process consisting of inspection, modeling, and evaluation. The present paper implements a methodology for redesigning and repairing injection molding parts based on the frontal process for developing concepts. The proposed methodology helps in the validation through Computer-Aided Engineering (CAE) in the designing stage using CAD software, ensuring the quality of the repair. Furthermore, the redesigned development has been carried out in the best way to obtain a better cooling, robustness, or plastic flow. In this research is implemented the proposed methodology in a Hot Runner System. Furthermore, a numerical simulation for three cases to evaluate the heat transfer and cooling times performed, finding the main differences in heat transfer due to drilled or milled rectangular channels, minimizing the time to reach ejection temperature and mold/part temperatures

Wear Dry Behavior of the Al-6061-Al2O3 Composite Synthesized by Mechanical Alloying

The present research deals with the comparative wear behavior of a mechanically milled Al-6061 alloy and the same alloy reinforced with 5 wt.% of Al2O3 nanoparticles (Al-6061-Al2O3) under different dry sliding conditions. For this purpose, an aluminum-silicon-based material was synthesized by high-energy mechanical alloying, cold consolidated, and sintered under pressureless and vacuum conditions. The mechanical behavior was evaluated by sliding wear and microhardness tests. The structural characterization was carried out by X-ray diffraction and scanning electron microscopy. Results showed a clear wear resistance improvement in the aluminum matrix composite (Al-6061-Al2O3) in comparison with the Al-6061 alloy since nanoparticles act as a third hard body against wear. This behavior is attributed to the significant increment in hardness on the reinforced material, whose strengthening mechanisms mainly lie in a nanometric size and homogeneous dispersion of particles offering an effective load transfer from the matrix to the reinforcement. Discussion of the wear performance was in terms of a protective thin film oxide formation, where protective behavior decreases as a function of the sliding speed