【作者】 陈仁宗；

【导师】 赵平；

【作者基本信息】 西华大学 ， 材料加工工程， 2010， 硕士

【摘要】 随着石化能源枯竭,以及温室效应加重,人类迫切需要新能源的应用,因此核能成为首选的新能源。人类利用原子能技术的日趋成熟,核电站及其他核设施的数量和规模日益扩大,鉴于辐射屏蔽体系在反应堆中的重要作用,屏蔽材料的研究与开发成了世界各国的热点。不仅仅表现为国家的大量投入,各国专家和学者也对这一课题产生了浓厚的兴趣。而10B优异的核特性,使得研究者们在开发新的屏蔽材料时从来就没有把关注的目光从它身上移开。在这些含B的屏蔽材料中,含硼铝铜合金以其良好的机械性能、特别是良好的韧性,成为了辐射屏蔽体系中结构材料的补充。然而国内外的辐射屏蔽多采用硼钢硼铁的形式,基体中铁硼化合物的脆硬性导致硼钢和硼铁冲击韧性不好。硼铝合金屏蔽用材料良好的力学性能正好是这些屏蔽材料的有益补充,国外已有尝试。本课题正是希望能开发新的低成本高性能含硼铝铜合金屏蔽用材料提供一些科研资料。本试验利用真空感应炉熔炼铝铜硼合金,采用ICP法分析制备合金的化学成分,用OLYMPUS型金相显微镜及S3400N型电子扫描电镜观察铸态及热处理态制备试样的显微组织,并结合STA-300HV型扫描探针显微镜进一步分析试样微区成分的变化。试验结果表明:采用一次性加入炉料,制备出的含硼量为小于1.0wt%的含硼铝铜合金,真空熔炼硼的收得率优于非真空熔炼硼的收得率,真空熔炼的铸件成分较纯净,硼化物夹杂较少,但在熔炼过程中,会有硼化物沉淀在坩埚壁上,同时还会有硼的挥发。基体结构组织主要为α相和θ相(Al2Cu),当加入硼后,会有硼化物生成,夹杂在基体的晶界处。硼含量的增加,使硬度增大,使θ相(Al2Cu)逐渐由网状变为断续网状和孤立状,也使AlB2的弥散相数目在增多。铁加入铝铜硼合金中,组织形态发生改变网状的θ相(Al2Cu)变成弥散状,生成针状的硬质化合物(FeAl3),并生成块状的Fe2B。加入1%钛铁后,生成块状的TiB2,θ相又变成网状,其中网状的θ相一部分仍Al2Cu,另一部分变为Al7Cu2Fe等含铁化合物,当加入1.5%Fe和2.2%Ti后组织中θ相变为鱼骨状和菊花状,一部分仍保持半孤立网状,鱼骨状在组织中主要是Al7Cu2Fe等含铁化合物。对加入不同元素铝铜合金固溶后,硬度发生明显不同。Al-Cu-B合金随着固溶时间延长,硬度逐渐提高,15h、24h出现两个硬度峰值。加入铁或钛铁后的Al-Cu-B合金固溶随时间延长,硬度没有变化。Al-Cu-B合金时效后,在270min出现最大硬度,比铝铜合金慢30min。更多还原

【Abstract】 With the depletion of fossil fuels, and the increase of the greenhouse effect, Human urgent the application of the new energy, therefore the nuclear energy was taken as the preferred new energy. The use of nuclear technology has matured, and the number and size of nuclear power plants and other nuclear facilities is growing, studying and developing shielding materials has become the world’s hot spots ,in view of radiation shielding system’s play important role in the reactor. This displayed not merely for the national massive input , but also for the nationals experts and scholars had a strong interest on the topic. However,The outstanding nuclear properties of 10B, cause the researchers has never been to pay attention away from it aside. In these shielding materials with B, boron -aluminum -copper alloy for its good mechanical properties, especially good toughness, as a complement of the radiation shield system structural materials . However, in the domestic and international the use of radiation shielding mainly in the form of iron boron or steel boron, the iron boron compounds‘s hard brittle of matrix cause iron boron steel and boron poor impact toughness. Boron Aluminum alloy shielding structural materials used exactly the complements of these shielding materials, has been tried abroad. This study is precisely hoped to like to provide some scientific research materials and information to develop a new low-cost boron-containing constructional shielding (the boron-containing Aluminum copper alloy).In this study, the vacuum inductance furnace is used to smelt aluminum-copper-boron alloy. the ICP method is used to analysis the chemical composition of the prepared alloy, the OLYMPUS metallographic microscope and the S3400N SEM are used to observe as cast structure and the heat-treated structure of the prepared aluminum-copper-boron alloy sample, and the change of the samples’micro-area composition is further analysised in conjunction with the STA-3100N EDS.The test results show that: vacuum smelting absorption rate of boron is better than with the non-vacuum melting, the boron-containing aluminum-copper alloy through adopting the craft that putting in burden one-time, prepared by the boron content of less than 1.0wt% of the boron-containing aluminum-copper alloy. The casting of vacuum melting has very little borides Inclusions; The casting of vacuum melting has the purer components; In the smelting process, there will be boride precipitation in the crucible wall, while there will be volatile boron. the main Structural organization of matrix for theαphase andθphase (Al2Cu),when the boron added into the alloy, the Boride will be generated, mixed in the grain boundaries of the matrix. With the increase of boron content, the hardness will be increase, so thatθphase (Al2Cu) gradually become half-mesh network and isolate state ,so the number of the dispersed phase AlB2 will be increased.Adding iron into aluminum copper boron alloy, the morphology will be changed.θphase (Al2Cu) from the net shape change into a dispersion state, generated Needle-like rigid compounds(FeAl3), and generated bulk of Fe2B.Adding 1% titanium and iron, will be generated block of TiB2,θphase has become a net shape. Parts of net shape’sθ-phase is still Al2Cu, another part of the iron compounds into such as Al7Cu2Fe Iron compounds. When adding 1.5% Fe and 2.2% Ti-phase ,θphase of the organization becomes daisy-like or fish bones -like, some still remain semi-isolated network, the organization of the fish bones–like mainly is Al7Cu2Fe such iron compounds.After the aluminum copper alloys add with different elements Solid solution, the hardness of change obvious difference. as the Al-Cu-B alloy Solid solution time went on ,the hardness gradually increased , 15h、24h has two maximum hardness, after the iron or titanium iron add into Al-Cu-B alloy, As Solid solution time went on , the hardness does not any change. If Al-Cu-B alloy time ageing, the maximum hardness will appears in 270min, slower than the aluminum-copper alloy 30min.更多还原