The Flame Retarding and Smoke Suppression of Flexible PVC
The purpose of this paper is to present an overview of the various technologies used to flame retard and smoke suppress PVC. It gives guidelines on how to formulate PVC using these additives and also discusses the effects these additives have on the physical properties, heat stability and processibility of PVC compounds using them. It is impossible to discuss every aspect of the flame retarding and smoke suppressing of PVC in a paper designed to be presented in a 30-minute talk. However, this paper offers both beginning and experienced formulators useful information in this area.
Flame retardants and smoke suppressants for flexible vinyl compounds
This paper reviews a number of technologies employed to reduce flammability and suppress smoke in flexible vinyl compounds. Advantages and disadvantages of the various systems are discussed, along with postulated mechanisms of action. Typical applications, approximate market prices, and major suppliers are also listed.
Failure analysis for poor solderability of Au surface of PCB
Nonwetting is one of the common problems and is always rejected in electronic assemblies. ENIG pads of a PCBA exhibited nonwetting after lead-free reflow soldering. With the aid of stereomicroscope, SEM&EDS and XRF, a series of analysis was performed. And after visual inspection, surface and cross section analysis, thickness measurement and solderability test, it can be inferred that oxidation of plating surface was the main reason for nonwetting, and corrosion in Ni plating caused an adverse impact on solderalibity.