Lead alloys chemical cleaning

This material occurs as vanadium ore but is also found in petroleum oil. It is also used to make alloy steels and as a catalyst in many chemical reactions. Exposure to the metal occurs when oil-fired boilers are cleaned and manifests itself in eye irritation, shortness of breath, chest pain and cough. The tongue becomes greenish-black in colour. Severe cases may develop broncho-pneumonia. Removal from contact with the dust usually leads to rapid recovery. 

Early attempts to simply mix no-clean flux (developed for tin-lead) with lead-free solder alloys yielded miserable results. No-clean flux required reformulation for lead-free solder alloys in order to accommodate their unique characteristics. The chemical reaction between fee flux and fee solder alloy in fee paste affects fee rheological characteristics of fee solder paste (which is critical for printing performance). The differences in density between fee lead-free and tin-lead solder alloys mean feat fee metal loading of fee solder paste needs to be different. 

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