In this paper the tensile properties of both ordered and disordered Ni-24Fe and Ni-24Fe-0.03%B (wt%) alloys in gaseous hydrogen was investigated. The result shows that the ductility of the disordered Ni3Fe is signif...In this paper the tensile properties of both ordered and disordered Ni-24Fe and Ni-24Fe-0.03%B (wt%) alloys in gaseous hydrogen was investigated. The result shows that the ductility of the disordered Ni3Fe is significantly larger than that of ordered material in gaseous hydrogen. However, the ductility of ordered Ni3Fe doped with 0.03%B is nearly the same as that of disordered one indicating the obvious suppressing effect of boron on the H2-induced embrittlement. Based on the segregation behavior of boron in Ni3A1, it is proposed that the suppressing effect of boron in Ni3Fe on the H2-induced embrittlement is attributed to the segregation of boron on grain boundaries, thereby reducing the hydrogen diffusivity along the grain boundaries.展开更多
The effects of boron content (CB = 0-0.14%(mass fraction)) on the tensile properties and enviro mental embrittlement of ordered Ni-24%Fe (atom fraction)- B (Ni3Fe-B) alloys have been investigated using tensile tests i...The effects of boron content (CB = 0-0.14%(mass fraction)) on the tensile properties and enviro mental embrittlement of ordered Ni-24%Fe (atom fraction)- B (Ni3Fe-B) alloys have been investigated using tensile tests in vacuum and under gaseous hydrogen. The results indicate that, when CB < 0.06%(mass fraction), the tensile strength and elongation of the alloys in vacuum and gaseous hydrogen increase as CB in the ordered Ni3Fe-B alloy increases. The tensile strength and elongation are maximum, and the hydrogen embrittlement factor (IH) is minimum for the ordered Ni3Fe-0.06%B (mass fraction) alloy. Compared with the ordered B-free Ni3Fe alloy,IH of the ordered Ni3Fe-0.06%B (mass fraction) alloy decreases by 98.1%, and the fracture morphology of the alloy changes from fully intergranular to fully transgranular, when tested in gaseous hydrogen. A critical level of boron segregation at the grain boundaries of ordered Ni3Fe-B alloys is observed. The hydrogen embrittlement of ordered Ni3Fe- B alloys in gaseous hydrogen can be completely suppressed by boron atoms when CB ≥ 0.06%(mass fraction).展开更多
针对核电厂循环水冲洗泵盖板表面结构完整性破坏失效的工程问题,基于冷金属过渡技术(Cold metal transfer,CMT),开展了CuAl9Ni3Fe2铝青铜合金电弧增材修复工艺的研究。通过单层单道成形、单层多道搭接成形以及多层多道试验研究,确定并...针对核电厂循环水冲洗泵盖板表面结构完整性破坏失效的工程问题,基于冷金属过渡技术(Cold metal transfer,CMT),开展了CuAl9Ni3Fe2铝青铜合金电弧增材修复工艺的研究。通过单层单道成形、单层多道搭接成形以及多层多道试验研究,确定并固化了一套CuAl9Ni3Fe2铝青铜合金CMT增材修复工艺的关键参数;并借鉴已有成熟的核电设备制造工程实践,参考RCC-M规范要求,制定了该修复工艺的验证试验要求,明确了试验项目、试验标准及验收指标,并按要求完成试件的制备及试验。结果表明:采用研发的CMT增材修复工艺制备的熔敷金属外观成形优良,内部致密无缺陷且与母材熔合良好,力学性能与母材相当,各项试验结果均满足验收指标。可用于CuAl9Ni3Fe2铝青铜合金的CMT增材制造及修复。展开更多
The interaction of water vapor and oxygen with Ni 3(Al, Ti) and Ni 3Fe were investigated using Auger electron spectroscopy, X ray photo emission and thermal desorption. These studies showed that water dissociates on N...The interaction of water vapor and oxygen with Ni 3(Al, Ti) and Ni 3Fe were investigated using Auger electron spectroscopy, X ray photo emission and thermal desorption. These studies showed that water dissociates on Ni 3(Al, Ti) (001) and polycrystalline Ni 3Fe to produce atomic hydrogen above 200 K, while remaining intact when exposed to Ni 3(Al, Ti) (111). In addition, pre adsorbed or co adsorbed oxygen on these surfaces strongly suppresses hydrogen production due to water dissociation. It was shown that adsorbed oxygen reacts with water vapor to produce surface hydroxyls, thus quenching the production of atomic hydrogen. Recent studies revealed an unexpected embrittling effect of boron in Ni 3Al in dry hydrogen. Experiments were proposed to elucidate the different possible roles of boron.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 50371050, 50671057)
文摘In this paper the tensile properties of both ordered and disordered Ni-24Fe and Ni-24Fe-0.03%B (wt%) alloys in gaseous hydrogen was investigated. The result shows that the ductility of the disordered Ni3Fe is significantly larger than that of ordered material in gaseous hydrogen. However, the ductility of ordered Ni3Fe doped with 0.03%B is nearly the same as that of disordered one indicating the obvious suppressing effect of boron on the H2-induced embrittlement. Based on the segregation behavior of boron in Ni3A1, it is proposed that the suppressing effect of boron in Ni3Fe on the H2-induced embrittlement is attributed to the segregation of boron on grain boundaries, thereby reducing the hydrogen diffusivity along the grain boundaries.
文摘The effects of boron content (CB = 0-0.14%(mass fraction)) on the tensile properties and enviro mental embrittlement of ordered Ni-24%Fe (atom fraction)- B (Ni3Fe-B) alloys have been investigated using tensile tests in vacuum and under gaseous hydrogen. The results indicate that, when CB < 0.06%(mass fraction), the tensile strength and elongation of the alloys in vacuum and gaseous hydrogen increase as CB in the ordered Ni3Fe-B alloy increases. The tensile strength and elongation are maximum, and the hydrogen embrittlement factor (IH) is minimum for the ordered Ni3Fe-0.06%B (mass fraction) alloy. Compared with the ordered B-free Ni3Fe alloy,IH of the ordered Ni3Fe-0.06%B (mass fraction) alloy decreases by 98.1%, and the fracture morphology of the alloy changes from fully intergranular to fully transgranular, when tested in gaseous hydrogen. A critical level of boron segregation at the grain boundaries of ordered Ni3Fe-B alloys is observed. The hydrogen embrittlement of ordered Ni3Fe- B alloys in gaseous hydrogen can be completely suppressed by boron atoms when CB ≥ 0.06%(mass fraction).
文摘针对核电厂循环水冲洗泵盖板表面结构完整性破坏失效的工程问题,基于冷金属过渡技术(Cold metal transfer,CMT),开展了CuAl9Ni3Fe2铝青铜合金电弧增材修复工艺的研究。通过单层单道成形、单层多道搭接成形以及多层多道试验研究,确定并固化了一套CuAl9Ni3Fe2铝青铜合金CMT增材修复工艺的关键参数;并借鉴已有成熟的核电设备制造工程实践,参考RCC-M规范要求,制定了该修复工艺的验证试验要求,明确了试验项目、试验标准及验收指标,并按要求完成试件的制备及试验。结果表明:采用研发的CMT增材修复工艺制备的熔敷金属外观成形优良,内部致密无缺陷且与母材熔合良好,力学性能与母材相当,各项试验结果均满足验收指标。可用于CuAl9Ni3Fe2铝青铜合金的CMT增材制造及修复。
文摘The interaction of water vapor and oxygen with Ni 3(Al, Ti) and Ni 3Fe were investigated using Auger electron spectroscopy, X ray photo emission and thermal desorption. These studies showed that water dissociates on Ni 3(Al, Ti) (001) and polycrystalline Ni 3Fe to produce atomic hydrogen above 200 K, while remaining intact when exposed to Ni 3(Al, Ti) (111). In addition, pre adsorbed or co adsorbed oxygen on these surfaces strongly suppresses hydrogen production due to water dissociation. It was shown that adsorbed oxygen reacts with water vapor to produce surface hydroxyls, thus quenching the production of atomic hydrogen. Recent studies revealed an unexpected embrittling effect of boron in Ni 3Al in dry hydrogen. Experiments were proposed to elucidate the different possible roles of boron.