| 摘要 |
<p>Process for mfg. two-layer contacts comprises using a layer (1) with low burn-off on a carrier layer (2) which is solderable and/or weldable; layer (1) is a pressed layer of powdered refractory metal(s), their mixt., alloys or cpds., and is covered by a layer (2) of low m.pt. metal or alloy powder, followed by compaction of both layers and heating in inert gas or vacuum above the m.pt. of layer (2), so the measured amt. of layer (2) impregnates the pores of layer (1). The novelty is that during both pressing operations, a profiled upper punch is used possessing uniform grooves on its working surface, and the pressed compact is placed on a grooved ceramic plate for heat-treatment. Accurate contact dimensions can be obtd. using only one sintering operation, and subsequent, expensive machining operations can be eliminated. Layer (1) is pref. made of W, Mo and/or Re, forming the contact surface, and layer (2) is pref. Ag, Cu or their alloys.</p> |
