Fabrication and characterization of M2SnC (M = Ti, Zr, Hf and Nb)
Fabrication and characterization of M2SnC (M = Ti, Zr, Hf and Nb)
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DOI：
10.1016/s1359-6462(97)00288-1
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发表时间：
1997-11-15
影响因子：
6
通讯作者：
Tyagi, S
中科院分区：
文献类型：
--
作者：
Barsoum, MW;Yaroschuk, G;Tyagi, S
过渡金属/TiN碳化物的结构由Jeitschko和Nowotny在六十年代初和七十年代初首次报道，通式为M#NC的过渡金属/TiN碳化物的结构由Jeitschko和Nb在一系列关于通式为M&C的碳化物的论文中提出，即所谓的H相，其中X是B族元素(L-3)。H相是三元层状化合物，其中共享边缘的过渡金属碳化物八面体的层被B族元素的六方网状隔开。共鉴定出40多个H相(3)，过渡金属碳化物层的晶面有Al、Ga、In、Tl、Sn、Ge、Pb、S、As、Cd、Zn和P(3，7)。在最初的工作中，通过将含有适当摩尔比的元素的样品密封在真空石英管中并将其加热到800℃下数百小时(1，2)来合成含SRI的三元碳化物。对样品进行了粉末化、X射线分析，并计算了它们的晶格参数(表2)。据我们所知，自从Nowotny和同事最初的报告以来，文献中没有关于这些化合物的更多信息。因此，我们对它们的性质一无所知。我们对其中一些临时性质的初步结果表明，它们是具有多种独特性质组合的固体(4-7)。作为一类材料，它们的硬度相对较低(4-6 Gpa)，电导率较高(2-5x106SL‘-’)，并且像石墨一样易于加工。在1200摄氏度以上的温度下，它们以塑性变形，在该温度下屈服点相当高(>；100兆帕)。此外，Ti$ICZ对热冲击不敏感，具有良好的抗氧化性(1×10“kg2nl%V‘，在100℃时)，是一种良好的(43W/mK)导热材料(4)。这篇论文的目的有两个。第一个是描述一种加工技术，利用该技术，我们首次能够制备出四个已知的含锡H相的全致密的单相多晶样品：TizSnC，ZrzSnC，Hf$SNC，Nb$Nc。二是介绍了对这些化合物进行的一些初步的性质测量。
The structures of the transition metal/tin carbides with the general formula M# nC, where M= Ti, Zr, Hf and Nb, were first reported by Jeitschko and Nowotny in the early sixties and seventies in a series of papers that dealt with carbides with the general formula M&C, the so-called H-phases, where X is a B-group element (l-3). The H-phases are ternary layered compounds in which layers of edge-shared transition metal carbide octahedra are separated from each other by hexagonal nets of the B-group element. Over 40 H-phases have been identified (3), with the planes separating the transition metal carbide layers being as diverse as Al, Ga, In, Tl, Sn, Ge, Pb, S, As, Cd, Zn and P (3, 7). In the original work, the Sri-containing ternary carbides were synthesized by sealing samples comprised of the ‘elements in the appropriate molar ratios in evacuated quartz tubes and heating them to 800 C for multiple hundreds of hours (1, 2). The samples were powdered, X-rayed and their lattice parameters calculated (Table 2). To the best of our knowledge no additional information is available in the literature about these compounds since the original reports of Nowotny and co-workers. Consequently, nothing is known about their properties.Our initial results on some of these temaries have shown them to be solids with a combination of unique properties (4-7). As a class these temaries have relatively low hardnesses (4-6 GPa), high electrical conductivities (2-5 x lo6 SL’m-‘) and are as readily machinable as graphite. At temperatures above 1200 C they deform plastically with yield points that are quite high (> lOO MPa) for that temperature. In addition, Ti $ iCz is not susceptible to thermal shock, has good oxidation resistance (1 x 10” kg2nl% V’at 1OOO’C) and is a good (43 W/m K) heat conductor (4). The purpose of this paper is twofold. The first is to describe a processing technique by which we were able to fabricate, for the first time, fully dense, single phase polycrystalline samples of the four known Sn-containing H-phases, namely: TizSnC, ZrzSnC, Hf $ SnC, Nb $ nC. The second is to present some preliminary property measurements that were carried out on these compounds.