Formation mechanism of the segregation layer of reactive metals to the bonding interface in brazing alloy joining for metal/ceramics and structure cotrol of joining

(1)在激励温度下观察到陶瓷/金属电偶产生类似的热刺激电流(TSC)。使用的金属有铝、铜、钛、铂、钨和钼。用碳化硅、氧化铝、氧化锆、氮化硅、氮化铝和硼化锆作陶瓷材料。这些陶瓷/金属电偶在升温时产生电动势，这与传统的热电动势不同。这些温度是从相邻的陶瓷电导率的增加来观察的。这些极化曲线与温度有关，但具有最大电动势。在钎焊温度以上，电动势在陶瓷一侧始终保持负电位。(2)用含有VIa族活性金属的钎料使活性元素在陶瓷界面上偏析。(3)为了解释这些偏析机理，我们假设这些电动势在钎焊温度下产生驱动力。。然后我们从电偶的外侧加电场。活性金属的偏析被陶瓷制成正极而消失。反面是隔离的。因此，我们解释了陶瓷/金属界面的偏析是由于陶瓷/金属界面上产生了特殊的热电动势所致。(4)陶瓷/金属界面偏析层厚度受外加小电流电场的控制。也就是说，层的厚度与电流和时间因素成正比关系。临时的。并不依赖于。

(1) Generation of like thermally stimulated current (TSC) was observed by using the couple was consisted ceramics/metal at elvated temperature. Metals were used Al, Cu, Ti, Pt, W and Mo. Ceramicses were used SiC, Al_2O_3, ZrO_2, Si_3N_4, AlN and ZrB_2. These ceramics/metal couples are generated electromotive force which is differntly character as conventional thermally EMF at elevate temperature. These temperature were observed from adjacent to increasing of electroconductivity of ceramics. These polarization curves has been depended temperature but has been maximum EMF. EMF are held always negative potential on side of ceramics above brazing TEMP. As 1100 k.(2) Reactive element are segregated on the interface of ceramics by using brazers which is included reactive metal such as VI a family Ti, Zr, Hf.(3) For explain these segregation mechanism, we are assumed that these EMF be made make driving force are generated ag brazing TEMP. . Then we are added electric field from out side of couple. Segregation of reactive metals are disappeared by ceramics are made positive pole. Reverse are segregated. Therefore, we are explained that segregation to the interface of ceramics are caused by generation of peculiary thermally EMF on interface ceramics/metal couple.(4) Thickness of segragation layer are controlled by outside electric field with small current. Namely, thickness of layer are propotionaly depended by factors of current and time. TEMP. Are not depended.