Mechanické vlastnosti ADI v závislosti na podmínkách tepelného zpracování

Mechanical properties of ADI in Dependence on Heat tratment Conditions

článek ve sborníku ve WoS nebo Scopus

en

The purpose of submitted work is completion pieces of knowledge about influence of structure and heat treatment contidions on static mechanical properties of austempered ductile cast iron. Owing to its excellent mechanical as well as technological properties, austempered ductile iron (ADI) belongs among very prospective structural materials. Recently it is applied in automobile and oil industry, and a considerable part of ADI production is applied also in military industry . ADI can replace steel in forged pieces, workpieces or weldments and nodular cast iron with lower level of strength properties in castings, as a rule with high economic or quality effects. The structure of ADI matrix is usually created by bainite with high strength and by stabilized austenite with high deformability. Their portion and partially also their properties are determined by transformation conditions, i.e. the temperature and the time of isothermal transformation while the austenitization conditions play only a marginal role.

Izotermicky zušlechtěná tvárná litina, v současné době nazývaná ADI (austempered ductile iron), patří mezi perspektivní konstrukční materiály, zejména pro dynamicky namáhané strojní součásti. Její vlastnosti je možno ve velmi širokém rozsahu ovlivňovat podmínkami režimu tepelného zpracování. Zatímco podmínky austenitizace nehrají významnější roli, podmínky izotermické transformace, t.j. transformační teplota a doba výdrže na této teplotě, ovlivňují výslednou strukturu matrice ADI a tím i její mechanické vlastnosti zásadním způsobem. Předložená práce je věnována studiu vlivu doby izotermické transformace v rozsahu 2 min až 9 h na strukturu, statické i únavové vlastnosti nelegované ADI získané při teplotě transformace 380 °C.

The purpose of submitted work is completion pieces of knowledge about influence of structure and heat treatment contidions on static mechanical properties of austempered ductile cast iron. Owing to its excellent mechanical as well as technological properties, austempered ductile iron (ADI) belongs among very prospective structural materials. Recently it is applied in automobile and oil industry, and a considerable part of ADI production is applied also in military industry . ADI can replace steel in forged pieces, workpieces or weldments and nodular cast iron with lower level of strength properties in castings, as a rule with high economic or quality effects. The structure of ADI matrix is usually created by bainite with high strength and by stabilized austenite with high deformability. Their portion and partially also their properties are determined by transformation conditions, i.e. the temperature and the time of isothermal transformation while the austenitization conditions play only a marginal role.

Podmínky izotermického zušlechtění, mechanické vlastnosti, ADI

Isotheram heat treatment conditions, mechanical properties, ADI

2005

20.09.2005

Brno University of Technology

Brno

80-214-2984-4

Juniormat 2005

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