Forming an erosion resistant coating on an electrode

摘要

An erosion resistant coating is formed on an electrode 10, (eg. of a spark plug) by causing an adhesively coated web 36 which contains an erosion resistant material to adhere to a pre-selected area of the electrode and heating the electrode/web combination to drive off the adhesive and fuse the erosion resistant material to the electrode. The erosion resistant material is platinum and boron is added to depress its melting point. These are formed into the web with a suitable matrix material and adhesive, both of which are heat decomposable or volatisable.