Protection structure for zirconium element outer electrode lead of oxygen sensor and preparation method of protection structure

Abstract

The invention discloses a protection structure for a zirconium element outer electrode lead of an oxygen sensor and a preparation method. A ceramic material protection layer is arranged in a sealed surface area of a zirconium element, the ceramic material protection layer is provided with an insulation material protection layer, and the insulation material protection layer and the ceramic material protection layer cover an outer electrode lead in the sealed surface area to form an outer electrode lead protection structure. The characteristics of the first protection layer (ceramic material protection layer) is completely consistent with that of a matrix material, by virtue of a primary sintering process, the first protection layer and a matrix are difficult to separate, and the outer electrode lead is well protected; the second protection layer (the insulation material protection layer) is insulated at a high temperature, after endurance for a long time, even if the second protection layer is separated from the first protection layer, the outer electrode lead is not influenced, and the second protection layer is tightly compressed, so that the insulation performance is not influenced; and the protection and insulation problem of the sealed area of the tubular zirconium outer electrode lead can be well solved, and the durability and reliability of a product are remarkably improved.

Description

technical field [0001] The invention relates to an oxygen sensor for an internal combustion engine, in particular to a protection structure for an outer electrode lead wire of an oxygen sensor zirconium element and a preparation process thereof. Background technique [0002] The oxygen sensor is used for closed-loop control of the engine, so as to ensure that the emissions of HC, CO and NOx during the life of the vehicle meet the regulatory requirements. This has played a vital role in reducing vehicle pollutant emissions and reducing environmental pollution. Zirconia oxygen sensors take advantage of the solid electrolyte properties of zirconia, which is conductive to oxygen ions at high temperatures. In this way, when the oxygen concentration on both sides of the zirconia, that is, the oxygen partial pressure, is different, the effect of oxygen ions migrating from one side to the other will occur, thereby generating a voltage signal. Specifically, the oxygen ion conductiv...

AI Technical Summary

Problems solved by technology

This will bring two problems: one is that the outer electrode will be broken due to the high pressure on the sealing surface, resulting in product failure; another problem is that the outer electrode will conduct with the sensor shell, and further conduct with the body, causing The Influence of the Interference Signal of the Vehicle Body on the Sensor Signal

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