Slévárenské metody výroby porézních kovů s pravidelnou buňkovou strukturou

Abstract

This dissertation thesis describes the proposal for technology of production of porous metal using casting methods. Porous metal is formed by intentional pore formation, which have various size, shape with regular or stochastic texture. These pores give metal many outstanding qualities, for example: high rigidity at low temperature, high thermal conductivity, energy absorption capacity etc. Since the discovery of porous metal materials there have been developed a lot of methods to produce them. The aim of this work is to verify selected casting method in production of porous metal with ordered internal structure. Porous metal, which is formed by infiltrating the liquid metal into the cavity of the mould, filled with a preform seems to be the fastest and most economical way. Despite that we cannot do it without the right production parameters. The process was optimized after the first castings of porous metal with ordered internal structure in a shape of the block, which had been created and the produced samples were evaluated according to their mechanical attributes during compression test to be used as an element in deformation zones. Computer software ASYS 18 was used as a tool to calculate heat transfer values for porous metal to be used as a heat exchanger. According to the results optimal cavity geometry has been designed. Subsequently 3D model of actual casting was made using Rhinoceros 4.0 for numerical simulation in software MAGMASOFT 5.4, where the whole process of production was designed and optimized. Based on this research a functional sample of porous metal with an ordered internal structure was made - a heat exchanger was produced. This heat exchanger made from aluminium alloy was casted to the sand form from (green sand) using preforms. Moreover, a porous metal casting with ordered internal lattice structure was produced. This casting was produced using Lost Foam method. The process was also optimized and products were evaluated for their mechanical features by compression test. The main aim of this research is to verify production of casts, which could be used in construction of vehicles in the field of impact energy absorption and as well as in energy as a heat exchanger.