HRXRD study of the theoretical densities of novel reactive sintered boride candidate neutron shielding materials
HRXRD study of the theoretical densities of novel reactive sintered boride candidate neutron shielding materials
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DOI：
10.1016/j.nme.2020.100732
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发表时间：
2020
影响因子：
2.6
通讯作者：
Jessica M. Marshall;David Walker;Pam A. Thomas
中科院分区：
文献类型：
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作者：
Jessica M. Marshall;David Walker;Pam A. Thomas
反应烧结硼化物(RSB)是一种由FeCr基硬质合金(FeCrCWCS)制备的新型碳化硼材料，作为球形托卡马克的致密辐射装甲显示出巨大的前景(Humphry-Baker，2007[1]，[2]，[3]，[4]，[5]。用高分辨X射线衍射仪(XRD)、电感耦合等离子体(ICP)、能谱分析(EDX)和扫描电子显微镜(SEM)对6种候选成分(4种RSB、2种CWCS)进行了评价，以确定其原子组成、物相存在和理论密度。当B含量为30at%时，通过烧结形成稳定的RSB颗粒。所有RSB组分都显示出相对于表面的剥离和碳富集性，这与粘结剂去除不佳和烧结时间不足相一致。粉末X射线衍射法得到的RSB中的相丰度主要由铁-钨-硼化物(FeWB/FeW2B2)、钨-硼(W2B5/WB)和铁-硼化物组成。就物理性能和最高的ρ/ρ理论而言，最佳的反应烧结成分(B5T522W)具有ρTheo=112.59±0.01g cm−3(ρ/ρTheo=999.3%)，并且其重量和后烧结W：B：Fe丰度接近1：1：1。这项工作表明，尽管RSB材料具有新颖性，但它们可以进行优化，原则上可以使用现有的CWC工艺路线进行加工。
Reactive Sintered Borides (RSBs) are novel borocarbide materials derived from FeCr-based cemented tungsten (FeCr-cWCs) show considerable promise as compact radiation armour for proposed spherical tokamak (Humphry-Baker, 2007 [1], [2], [3], [4], [5]. Six candidate compositions (four RSBs, two cWCs) were evaluated by high-resolution X-ray diffraction (XRD), inductively coupled plasma (ICP), energy dispersive X-ray analysis (EDX) and scanning electron microscopy (SEM) to determine the atomic composition, phase presence, and theoretical density.RSB compositions were evaluated with initial boron contents equivalent to 25 at%<x< 40 at%. Stable RSB bodies formed from sintering for compositions where B at%>30 at%. All RSB compositions showed delamination and carbon enrichment in the bulk relative to the surface, consistent with non-optimal binder removal and insufficient sintering time. Phase abundance within RSBs derived from powder XRD was dominated by iron tungsten borides (FeWB/FeW2B2), tungsten borides (W2B5/WB) and iron borides. The most optimal RSB composition (B5T522W) with respect to physical properties and highestρ/ρtheohadρtheo= 12.59 ± 0.01 g cm−3forρ/ρtheo= 99.3% and had the weigh-in and post-sintered W: B: Fe abundance closest to 1: 1: 1. This work indicates that despite their novelty, RSB materials can be optimized and in principle be processed using existing cWC processing routes.