Zr-4合金表面耐事故Cr涂层制备及组织性能

Microstructure and Properties of Accident Tolerant Cr Coating Synthesized on Zr-4 Alloy

采用等离子增强物理气相复合沉积技术,在Zr-4合金表面制备了Cr复合涂层,并在涂层沉积之前对涂层与基体的界面进行了Cr离子的轰击注入强化。结合锆合金包壳的实际使用工况,设计试验方法,评价表征了涂层体系的各项性能及其对锆合金基体的影响。高温蒸气加速腐蚀试验表明,相比于无涂层Zr-4基体试样,Cr涂层明显阻碍了氧向Zr-4基体内部的扩散,并有效抑制了基体内部有害氢化物的生成。在模拟事故的高温(>1000℃)热冲击条件下,相比于无涂层基体表面较厚氧化物生成的现象,涂层样品并未出现脱落,基体也并未出现氧化腐蚀。拉伸及内压爆破测试表明,样品表面Cr涂层表现出与基体较好的附着力,未出现沿破裂界面的脱落,也未影响Zr-4基体的拉伸及室温爆破性能。可以认为,Zr-4合金表面Cr涂层是理想的耐事故涂层材料之一。

Cr coating was prepared on the surface of Zr-4 alloy by plasma enhanced physical vapor deposition technology,and the interface between coating and substrate was bombarded and strengthened by Cr ion before coating deposition.The properties of the coating system and its influence on the zirconium alloy matrix were evaluated.The high temperature steam accelerated corrosion test results show that compared with the uncoated Zr-4 alloy substrate sample,the diffusion of oxygen into the Zr-4 alloy substrate is obviously hindered and the formation of harmful hydrides in the substrate is effectively inhibited.The Cr coated sample does not fall off,and the substrate is not oxidized in the high temperature(>1000℃)thermal shock test,but the uncoated substrate is totally oxidized.The tensile and internal pressure blasting tests results also show that the Cr coating exhibits good adhesion to the Zr-4 substrate,with little effects on mechanical properties of Zr-4 substrate.It can be considered that the Cr coating is one of the ideal accident-tolerant coating materials on Zr-4 cladding.