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通过实验测试及动力学机制方程拟合, 研究了放电等离子烧结Zr-xCu (x=0, 5%, 10%, 质量分数)合金吸氘动力学机制. 结果表明, 随着合金元素Cu的加入, 相结构由纯Zr的a-Zr单相转变为Zr-Cu合金的a-Zr和Zr₂Cu双相. 相应地, 其吸氘达到饱和的时间逐渐延长, 由纯Zr的20 min增加到Zr-5%Cu的80 min和Zr-10%Cu的130 min, 吸氘后的纯Zr相结构为氘化物e, 而Zr-Cu合金相结构为e相、Zr₂Cu和Zr₇Cu₁₀. 动力学机制方程拟合结果显示, 纯Zr吸氘过程受二维扩散机制控制, 而Zr-Cu合金吸氘过程受化学反应机制控制. Cu的加入改变了其吸氘机制, 从而降低了吸氘速率.

With increasing demand for energy, nuclear fusion has attracted more and more attention. In fusion process, the most promising of fusion reactions is the fusion of deuterium and tritium. Thus, deuterium absorption has become a key issue. At present, the extensively used materials for storage and supply of deuterium are uranium beds. However, upon hydrogenation, uranium is easily disintegrated into fine powder, which causes many undesirable problems. It has been found that zirconium alloys can take as much deuterium atoms as that of uranium alloys but with a lower density and price, thus becoming a candidate material for deuterium carrier. However, zirconium alloys usually occur to crack after deuterium absorption, which badly restricts their application as a deuterium carrier. In order to minimize the cracking, Cu is chosen as an alloying element, expecting to minimize the cracking. In this work, the kinetic mechanisms of deuterium absorption in Zr-xCu (x=0, 5%, 10%, mass fraction) alloys were investigated based on experiments and kinetic function calculations. The results show that with the increase of Cu content, the microstructure transforms from the primary single a-Zr phase of the pure Zr to the a-Zr and Zr₂Cu duplex phases of the Zr-5%Cu and Zr-10%Cu alloys. Correspondingly, the equilibrium time of deuterium absorption increases significantly from 20 min for the pure Zr to 80 min for the Zr-5%Cu alloy and to 130 min for the Zr-10%Cu alloy. After deuterium absorption, the phase of pure Zr is e deuteride while the phases of Zr-5%Cu and Zr-10%Cu are e deuteride, Zr₂Cu and Zr₇Cu₁₀. The kinetic mechanisms of deuterium absorption in these alloys are found to be controlled by a 2-dimensional diffusion mechanism in the pure Zr, and by a chemical reaction mechanism in the Zr-5%Cu and Zr-10%Cu alloys. The addition of Cu changes the kinetic mechanisms of the Zr-xCu alloys, resulting in slowing down deuterium absorption rate. It is attributed that during deuterium absorption of Zr-Cu alloys, Zr₂Cu also absorbs deuterium and forms intermediate phase, such as Zr₂CuH_x. Then the intermediate phase will discompose into Zr₇Cu₁₀ and ε deuteride.