Nb／Al2O3钎焊界面的网状分割效应

首次研究了在Ａｌ２Ｏ３陶瓷与金属Ｎｂ的钎焊面之间加入一层金属Ｍｏ网，可大幅度提高接头的焊接强度，经用Ｎｉ５１Ｔｉ４９和Ｃｕ５２Ｎｉ１８Ｔｉ３０两种钎料焊接，焊后强度均提高５０％以上，断裂特征由陶瓷中的大块破损转变为沿界面的混合型断裂。金属网的加入对钎料凝固收缩应力产生了分割相消的作用，从而有效降低了焊接接头的残余应力。

Dividing Effect of a Net Interface in the Nb/Al 2O 3 Interface

The effect of a molybdenum net interlayer in the interface between Al 2O 3 and Nb on the shear strength of the brazed joint is investigated. The existence of the net in Al 2O 3/Nb brazed interface could greatly increase the shear strength of the brazed joint. As compared with the fracture of stripped off large pieces of ceramics from the interface of those brazed joints without the molybdenum net interlayer, the fracture of brazed joints with the molybdenum net interlayer changes into a mixed type of fracture occured along the interface. A dividing effect of the net during solidification contraction of the interface greatly decreases the residual stress in the brazed joint. The improvement in the fracture behavior of the brazed joint with molybdenum net interlayer is caused by the dividing effect.