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The product design and engineering by companies, especially SMEs (small and medium enterprises), is a key competitive factor. The Brazilian industrial sector lacks a systematic approach that integrates different variables required by the market in order to help determine product excellence. It is a way to reduce the economic differences between regions in the country. This paper brings a contribution to this goal, presenting the development process and first results of an Integrated Laboratory for Product Design (LIDEP). The LIDEP works through a multidisciplinary and systemic approach, developing new products from existing demand and transferring technologies on design methodology, prototyping and design management to local SMEs and educational institutions. The LIDEP initiative is developed in Montes Claros, an important city in the northern of Minas Gerais state, providing competitive conditions to local SMEs by adding significant value to products by making use of systemic design, market analysis and leveraging technical regulations.

Tento článek zkoumá vliv velikosti původního austenitického zrna během procesu kalení a přerozdělení (Q-P) na finální mechanické vlastnosti Q-P oceli. Rozdíly v rozložení velikosti austenitické zrna mohou způsobit např. nerovnoměrnou rychlost ohřevu polotovarů před kovacím procesem. Za účelem kvantifikování tohoto vlivu bylo na válcových vzorkách z oceli 42SiCr provedeno definované tepelné zpracování na dilatometru. Rozdílná velikost austenitická zrna byla dosažena tepelným zpracováním, které předcházelo vlastnímu Q-P procesu. Výsledné mechanické vlastnosti byly popsány zkouškou tlakem a odpovídající mikrostruktura byla analyzována pomocí skenovacího elektronového mikroskopu (SEM). This paper examines how the initial austenite grain size in quench and partitioning (Q-P) processes influences the final mechanical properties of Q-P steels. Differences in austenite grain size distribution may result, for example, from uneven heating rates of semi-finished products prior to a forging process. In order to quantify this influence, a carefully defined heat treatment of a cylindrical specimen made of the Q-P-capable 42SiCr steel was performed in a dilatometer. Different austenite grain sizes were adjusted by a pre-treatment before the actual Q-P process. The resulting mechanical properties were determined using the upsetting test and the corresponding microstructures were analyzed by scanning electron microscopy (SEM). These investigations show that a larger austenite grain size prior to Q-P processing leads to a slightly lower strength as well as to a coarser martensitic microstructure in the Q-P-treated material.