Przyszlak Natalia, Wróbel Tomasz, Dulska Agnieszka, Nuckowski Paweł M, Łukowiec Dariusz, Stawarz Marcin
Department of Foundry Engineering, Silesian University of Technology, 7 Towarowa Street, 44-100 Gliwice, Poland.
Materials Research Laboratory, Faculty of Mechanical Engineering, Silesian University of Technology, 18A Konarskiego Street, 44-100 Gliwice, Poland.
Materials (Basel). 2024 Dec 4;17(23):5933. doi: 10.3390/ma17235933.
The research conducted in this study aimed to determine whether the production of a layered casting in the material system of X46Cr13 steel (working part) and gray cast iron (base part) can be integrated with the hardening process of this steel within the conditions of the casting mold. Accordingly, a series of layered castings was produced by preparing the mold cavity, where a monolithic steel insert was poured with molten gray cast iron with flake graphite. The variable factors in the casting production process included the pouring temperature T and the thickness of the support part g. Importantly, given that the hardening of the X46Cr13 steel insert occurred directly within the mold, the selection of casting parameters had to balance the ability to heat the insert to the austenitization temperature Tγ while also creating thermokinetic conditions conducive to the rapid cooling of the system. Therefore, chromite sand-commonly regarded as a rapid-cooling material-was selected as the matrix for the molding material. Based on the conducted studies, it was determined that the thermokinetic properties of this material allowed the surface of the cast working part to be heated to the austenitization temperature. The microstructure consisted of Cr(Fe) carbides within a martensitic-pearlitic matrix, with martensite filling the grains of the primary austenite and pearlite situated along their boundaries. The carbides were primarily located at grain boundaries and, to a lesser extent, within the primary austenite grains. Through transmission electron microscopy and X-ray diffractometry, the type of Cr(Fe) carbide in the microstructure of the working part was identified as MC.
本研究开展的实验旨在确定，在铸模条件下，由X46Cr13钢（工作部件）和灰铸铁（基体部件）组成的材料系统中生产分层铸件的工艺，能否与该钢的淬火工艺相结合。因此，通过准备型腔制作了一系列分层铸件，在型腔内，将整体钢质镶块浇铸上带有片状石墨的熔融灰铸铁。铸造生产过程中的可变因素包括浇铸温度T和支撑部件的厚度g。重要的是，鉴于X46Cr13钢质镶块的淬火直接在铸模内进行，铸造参数的选择必须在将镶块加热到奥氏体化温度Tγ的能力与创造有利于系统快速冷却的热动力学条件之间取得平衡。因此，通常被视为快速冷却材料的铬铁矿砂被选作造型材料的基体。基于所开展的研究，确定该材料的热动力学特性使铸造工作部件的表面能够被加热到奥氏体化温度。微观结构由马氏体-珠光体基体中的Cr(Fe)碳化物组成，马氏体填充在初生奥氏体的晶粒内，珠光体位于其晶界处。碳化物主要位于晶界，在较小程度上也存在于初生奥氏体晶粒内。通过透射电子显微镜和X射线衍射测定法，确定工作部件微观结构中的Cr(Fe)碳化物类型为MC。
