玻璃金属封接型电气贯穿件具有耐辐照、耐高压、气密性好、使用寿命长等优 点，是新一代核反应堆的优良之选。玻璃与金属结合的好坏直接影响到电气贯穿件 的性能。本课题研究了硼硅酸玻璃和 AISI 304 奥氏体不锈钢之间的化学结合强度 和机械结合强度，为提高核用电气贯穿件的封接性能提供了新的思路。本文通过对 AISI 304 奥氏体不锈钢在 1100°C下预氧化处理不同的时间，研究 了预氧化时间对硼硅酸玻璃与 AISI 304 之间化学结合强度的影响。XRD 及 TEM 测试结果表明预氧化膜化学组成主要包括 MnCr2O4、Cr2O3 和 SiO2，预氧化膜的形 貌随预氧化时间明显变化，但其化学组成不受影响。随着预氧化时间的延长，氧化 膜的厚度逐渐增加并且趋向均匀化。剪切强度测试表明封接界面的化学结合强度 随预氧化时间的增加而增强，在氧化时间为 50min 时达到最大值 27MPa，随后逐 渐降低。此种预氧化制度下得到的氧化膜具有三层结构:外层为连续的尖晶石氧化 物层，由 MnCr2O4 和少量 FeCr2O4、FeMn2O4 组成，中间层为连续的具有刚玉结构 的 Cr2O3 层，最内层为不连续的无定形态 SiO2 层。为提高封接界面的耐热老化性能，通过往硼硅酸玻璃里掺入 ZnO 对玻璃-金属 封接界面进行了改性。研究发现，在熔封过程中玻璃中的 Zn2+会扩散到氧化膜中 的尖晶石外层，占据尖晶石结构的四面体间隙位置，生成结构更稳定的 ZnCr2O4。 Zn2+的扩散覆盖了整个尖晶石外层，但没有进入 Cr2O3 层。Zn2+掺杂导致尖晶石外 层具有更紧凑的晶体结构，它可以有效阻碍热老化过程中氧化层内的 Fe、Mn、Cr 等元素向玻璃中的扩散，使得玻璃/氧化物界面的高温稳定性得到提高。为了提高玻璃金属压缩封接件的安全服役温度，研究了机械结合和化学结合 对封接件的高温气密性的影响。通过改变硼硅酸玻璃中碱金属氧化物的含量来调 控玻璃的热膨胀系数和预氧化物在玻璃中的溶解度。然后将硼硅酸玻璃与预氧化 后的 AISI 304 封接在一起，对封接件的化学结合强度和机械结合强度进行了研究。 实验结果表明，往玻璃里添加碱金属氧化物会改变玻璃的热膨胀系数，进而影响封 接件的机械压缩状态。玻璃和金属外壳热膨胀系数差越小，封接件能耐受的温度越 高。此外碱金属氧化物作为网络修饰体会改变金属基体氧化物在玻璃中的溶解度， 进而影响玻璃与金属之间的化学结合强度。随着碱金属含量的增加，硼硅酸玻璃与 AISI 304 之间的化学结合强度先增加再减少。对比机械压缩和化学结合对封接件 高温高压气密性的影响，发

The electrical penetration assemblies (EPA) which adopted glass-to-metal (GTM) seal are promising candidates for a new generation of nuclear reactors due to their distinct advantages including irradiation resistance, high pressure resistance, good hermeticity and long operating life. The performance of the EPA depends on the bonding between glass and metal. This paper studied the chemical bonding and mechanical compression between AISI 304 austenitic stainless steel and borosilicate glass, which provided new insight into improving the properties of the EPA.The AISI 304 austenitic stainless steel shells were pre-oxidized at 1100°C for 30, 40, 50, 60, 70 and 80 minutes respectively. The effect of pre-oxidation duration on the chemical bonding strength between borosilicate glass and AISI 304 was investigated. The obtained oxide film was mainly composed of MnCr2O4，Cr2O3 and SiO2. The pre- oxidation duration only affects the morphology of the oxide film rather than chemical composition. The thickness of the oxide film gradually increases and tends to be uniform with increasing pre-oxidation duration. And the chemical bonding strength of the seal increases at first and then decreases with increasing oxidation duration. It shows the highest shear strength (27MPa) at the pre-oxidation duration of 50 minutes. The morphology of this oxide film exhibits three layers structure, that is, the outer layer of spinel oxide composed of MnCr2O4 mixed with a small amount of FeCr2O4 and FeMn2O4, the middle layer of corundum-structure Cr2O3, and the inner layer of armophous SiO2.The borosilicate glasses with different ZnO additions were fabricated to join with the pre-oxidized AISI 304 samples. The effect of ZnO content on sealing performance was investigated. It was found that Zn2+ in the glass would diffuse into the outer spinel oxide layer in the oxide film and occupy a large proportion of tetrahedral sites in the spinel structure, resulting in a more stable Zn-rich layer. The Zn2+ modified spinel oxide layer shows a more compact crystal structure, which can suppress the diffusion behavior of elements (Fe, Mn, and Cr) from the oxides into the glass during the thermal aging process, contributing to a more chemically stable glass/oxide interface.To investigate the effect of alkali metal oxide in the glass on the high-temperature performance of the seal, the borosilicate glasses with different Na2O and K2O contents were fabricated, and then sealed with the pre-oxidized AISI 304 samples. The mechanical compression and chemical bonding of the seal were studied respectively. The result showed that the thermal expansion coefficient (TEC) of glass can be tuned by alkali metal oxide addition. Then the mechanical compression of the seal was influenced. The smaller the TEC difference between glass and metal, the higher the enduring temperature of the seal. In addition, the alkali metal oxide, acting as a network modifier, would change the solubility of metal matrix oxide in the glass, thereby affecting the chemical bonding strength between the glass and the metal. The chemical bonding strength increases at first and then decreases with the increase of alkali metal oxide content. Comparing the effect of chemical bonding and mechanical compression on the high-temperature and high-pressure hermeticity of the seal, it can be determined that mechanical compression is more critical to the high-temperature performance of the seal.