| 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. |
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