热处理对含钛镍铬合金、镍铬合金金瓷结合强度的影响

目的：探讨热处理对含钛镍铬（Ni?Cr?Ti）合金、镍铬（Ni?Cr）合金金瓷结合强度的影响和两种合金的金瓷界面特征。方法执行ISO9693标准，采用三点弯曲试验分别测定经减压热处理或未经热处理的含钛镍铬合金、镍铬合金的金瓷结合强度。运用扫描电镜和X射线能谱进行金瓷界面分析。结果金瓷结合强度分析结果显示：Ni?Cr?Ti减压热处理组为（38.04±3.79）MPa ，Ni?Cr?Ti无热处理组为（32.17±4.00）MPa ，Ni?Cr减压热处理组为（36.32±7.41）MPa，Ni?Cr无热处理组为（31.75±2.77）MPa。镍铬合金和含钛镍铬合金金瓷结合强度差异无统计学意义（F=0.500，P=0.484），但两种合金减压热处理后的金瓷结合强度均大于无热处理组（F=11.973，P=0.001）。扫描电镜和X线衍射结果显示，两种合金减压热处理组金属与瓷之间结合紧密，无热处理组金属与瓷之间可见裂纹及气泡。结论含钛镍铬合金与镍铬合金的金瓷结合强度接近，通过减压热处理可提高两种合金金瓷结合强度。

The effect of heat treatment on bonding strength of ceramic to cast nickel-chromium-based alloys

Objective To explore the effect of heat treatments on the metal?ceramic bonding strength in Ni?Cr?Ti al?loy and Ni?Cr alloy. Methods We evaluated the metal?ceramic bond strengths by using a three?points bending test ac?cording to ISO 9693. Meanwhile, we also observed the metal?ceramic interface through scanning electronic microscope (SEM) and energy dispersive spectrum (EDS). Results The mean value of bonding strengths of four groups were (38.04 ± 3.79) MPa (Ni?Cr?Ti, degassed), (32.17 ± 4.00) MPa (Ni?Cr?Ti, no heat treatment), (36.32 ± 7.41) MPa (Ni?Cr, de?gassed), (31.75 ± 2.77) MPa (Ni?Cr, no heat treatment). The statistic analysis showed that the mean bonding strengths were affected significantly by heat treatment method (P=0.001), but not alloy type (P=0.484). SEM and EDS demon?strated that the bonding surfaces of degassed specimens were compacted and had no cracks unlike those of specimens not receiving heat treatment. Conclusion According to the test results, the metal?ceramic bonding strengths of Ni?Cr?Ti alloy and Ni?Cr alloy are close to each other, and the bonding strengths of alloys can be heightened by heat treatment.