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论文类型：期刊论文

发表时间：2015-07-01

发表刊物：INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS

收录刊物：SCIE、EI

卷号：51

页面范围：130-136

ISSN号：0263-4368

关键字：Ceramic; Microstructure; Properties

摘要：The two batches of commercially available powders were used as raw materials to synthesize HfB2 powders. The synthesized HfB2 powders were heated at 450 degrees C for 10 mm in the flow of nitrogen and then quenched into liquid nitrogen. The results indicated the refinement effect of liquid nitrogen quenching on synthesized HfB2 powders was very obvious. The relative density values of HfB2 ceramics fabricated using micron and submicron HfB2 powders were less than 89.5% due to the presence of trace carbonaceous compound and more than 98.1% due to higher driving force for densification, respectively. The microstructure, mechanical properties and thermal shock resistance of HfB2 ceramics fabricated using micron and submicron HfB2 powders were investigated in detail. In particular, finite element analysis was used to explore the temperature and thermal stress distribution in the specimen in the course of thermal shock. (C) 2015 Elsevier Ltd. All rights reserved.